Longest run would be Action Comics with over 600 consecutive issues. I have over 600 issues each in singles of Superman and Action Comics.

Awesome collection Scott!

I don't really have many, since I always just kind of jumped off when the going got bad, but I have the full run of the Jack Knight Starman, every issue of Wolfman and Perez Titans until Perez leaves (I don't have all the issues he came back for later on), all of Crisis (Infinite and on Infinite Earths), JLA/Avengers, and, uh.... that's it, I guess.

I mean, I have both issues of Crimson Plague, but I don't think that really counts.

Where's the "like" button?

Ummm... a whole lot.

I don't have a big collection, but I have a few complete runs. I have the entire Classic X-Men series, which reprints the first 100+ issues of the Claremont run. These were among the first comics I started reading/collecting as a kid, and I just stuck with it since it was cheaper to get these than the original Uncanny issues. I also have a complete run of Uncanny starting from issue 206 to somewhere just before the Age of Apocalypse... mid 300s I think?  So between Classic and Uncanny, I have Claremont's entire X-Men run in single issues. That's probably far less impressive than having the entire run as issues of Uncanny, but I'll take it. 

Of the other X-books, I have a complete run of the first 70 or so issues of the Wolverine solo series.

I also have the entire first run of Frank-Miller-as-writer on Daredevil.  After that, I have an unbroken run from #227 to #310, which covers Miller's Born Again, the entire Nocenti run, and the beginning of D.G. Chichester's run.  After that, it's Kesel's run which is pretty short, and the entire Daredevil vol. 2 which covers the Smith, Bendis, Brubaker, and Diggle runs.  I also have the entire Waid run up until last week's issue.

I also have the complete run of Robotech: The Macross Saga and Robotech: The New Generation by Comico.  I was a big Robotech fan as a kid.  

Basically, my comic collection screams "the 80s".  

My longest unbroken run is Conan the Barbarian #25-275, I also have 1-4 and a few more before 25, in single issues and the ones I am missing in trade, but I am slowly tracking down the rest. Next would be X-Men/Uncanny which is unbroken from 131-356 when I dropped the X-Men altogether. Warlord runs 1-104 unbroken but missing a few between 105 and the end of the series. As for actual complete stuff, longest is Master of Kung Fu from Special Marvel Edition 15-MoKF 125. As for the rest, following Kurt's example of no one-shots...

Abe Sapien: The Drowning (Dark Horse): 1-5
Adam Strange (DC; ’04): 1-8
Agents of Atlas (Marvel; ’09): 1-11
Alan Moore’s Yuggoth Cultures and Other Growths (Avatar): 1-3
All-Star Comics (DC, 70's revival): 58-74
America vs. the Justice Society (DC): 1-4
Amethyst, Princess of Gemworld (DC; maxi): 1-12, Annual 1

Amethyst (DC): 1-16, Special 1

Amethyst (DC; ’87): 1-4

Angela (Image): 1-3

Annihilation Conquest (Marvel): Prologue; 1-6
Aquaman: Time and Tide (DC): 1-4

Arak, Son of Thunder (DC): 1-50, Annual 1

Arion, Lord of Atlantis (DC): 1-35; Special 1

Arion the Immortal (DC): 1-6

Avengers Forever (Marvel): 1-12

Avengers 1959 (Marvel): 1-5

Avengers vs. Atlas (Marvel): 1-4
Balder the Brave (Marvel): 1-4
Batman: Black & White (DC: ’13) 1-6

Batman: The Cult (DC): 1-4

Batman/Grendel: 1 (Devil’s Riddle), 2 (Devil’s Masque) (DC/Comico)
Batman: Nevermore (DC): 1-5
Beowulf (DC): 1-6

Beowulf (the comic.com): 1-3

The Black Beetle: No Way Out (Dark Horse): 1-4
Black Dragon (Marvel/Epic): 1-6
Blackhawk (DC; ’88): 1-3
Black Panther: Panther’s Prey (Marvel): 1-4
Bloodstone (Marvel): 1-4
The Book of Ballads and Sagas (Green Man Press): 1-4
‘Breed (Malibu/Bravura): 1-6

‘Breed II (Malibu/Bravura): 1-6

‘Breed III (Image): 1-7

Captain America: Sentinel of Liberty (Marvel): 1-12

Captain America Special Edition (Marvel): 1, 2

Challengers of the Unknown (DC; ’04): 1-6
Chiaroscuro: The Private Lives of Leonardo da Vinci (DC/Vertigo): 1-10
Cinder and Ashe (DC): 1-4
Claw the Unconquered (DC): 1-12
Conan and the Demons of Khitai (Dark Horse): 1-4

Conan and the Island of No Return (Dark Horse): 1, 2

Conan and the Jewels of Gwahlur (Dark Horse): 1-3

Conan and the Midnight God (Dark Horse): 1-5

Conan and the Songs of the Dead (Dark Horse): 1-5

Conan the Barbarian (Marvel; ’97): 1-3

Conan the Barbarian (Dark Horse; ’11): 1-25

Conan: The Book of Thoth (Dark Horse): 1-4

Conan: Flame and the Fiend (Marvel): 1-3
Conan: The Return of Styrm (Marvel): 1-3
Criminal: The Last of the Innocent (Marvel/Icon): 1-4
Crimson Plague (Image/Gorilla): 1, 2

Crisis on Infinite Earths (DC): 1-12

Danger Unlimited (Dark Horse): 1-4
Deadman (DC): 1-7

Deadman: Dead Again (DC): 1-5

The Death of the New Gods (DC): 1-8
Defenders (Marvel; ’12): 1-12
Devil Dinosaur (Marvel): 1-9

The Devil’s Footprints (Dark Horse): 1-4

Doc Savage (DC; ’87): 1-4
Doc Savage: The Man of Bronze (Millennium): 1-4

Dr. Fate (DC; ‘87): 1-4

Dr. Fate (DC; ’03): 1-5
Dr. Strange: Flight of the Bones (Marvel; Marvel Knights; ’99): 1-4
Dr. Strange: The Oath (Marvel): 1-5
Doctor Strange: Sorcerer Supreme (Marvel): 1-90, Annual 2-4
Doctor Voodoo: Avenger of the Supernatural (Marvel): 1-5
Doorway to Nightmare (DC): 1-5
Dreadstar (Marvel/Epic): 1-26, Annual 1

Dreadstar (First): 27-64

Dreadstar (Bravura/Malibu): ½, 1-6

Edge of Chaos (Pacific): 1-3
Elric: The Balance Lost (BOOM!): FCBD Ed.; 1-12

Elric: Sailor on the Seas of Fate (First): 1-7

The Eternals (Marvel): 1-19, Annual 1
Flash Gordon (DC): 1-9
The Fox (Archie/Red Circle; ’13): 1-5
Further Adventures of Indiana Jones (Marvel): 1-32
Giant-Size Conan (Marvel): 1-5
Giant-Size Master of Kung Fu (Marvel): 1-4
Green Arrow: The Long Bow Hunters (DC): 1-3
The Grimoire (Speakeasy): 1-7
Half PAst Danger (IDW): 1-6 
Hardcore Station (DC): 1-6
Hawkmoon: The Sword of Dawn (First): 1-4
The History of the DC Universe: 1, 2

The Hit (BOOM!): 1-4

The Hobbit (Eclipse): 1-3

H.P. Lovecraft’s Cthulhu (Millennium): 1-3
Immortal Iron Fist (Marvel): 1-27, Ann 1
, Orson Randall & the Death Queen of California, Orson Randall & the Green Mists of Death 
Immortal Weapons (Marvel): 1-5

Invasion (DC): 1-3
Jack of Hearts (Marvel): 1-4

James Bond: For Your Eyes Only (Marvel): 1-2

James Bond: Permission to Die (Eclipse): 1-3

Joe Kubert Presents (DC): 1-6

John Bolton’s Halls of Horror (Eclipse): 1, 2

Kull the Conqueror (Marvel; ’82): 1, 2

Kull the Conqueror (Marvel; ’83): 1-10

Legends (DC): 1-6
Legends of Red Sonja (Dynamite): 1-5
Logan’s Run (Marvel): 1-7
Madame Xanadu (DC/Vertigo): 1-29
Man of Steel (DC): 1-6
Martian Manhunter: American Secrets (DC): 1-3
Marvels (Marvel): 0, 1-4

The Marvels Project (Marvel): 1-8

Master of Kung Fu (Marvel): Special Marvel Edition 15, 16; MoKF: 17-125, Annual 1, Bleeding Black

Masterworks Series of Great Comic Book Artists (DC): 1, 2 (Frazetta), 3 (Wrightson)

Micronauts (Marvel): 1-59, Annual 1, 2

Micronauts (’84; Marvel): 1-20

Micronauts (Image): 1-11, 2002 Convention Preview

Micronauts (Devil’s Due): 1-3

Micronauts: Karza (Image): 1-4

Midnight Men (Marvel/Epic): 1-4

Monkeyman & O’Brien (Dark Horse): Special; 1-3
Mythstalkers (Image): 1-8
Nathaniel Dusk (DC): 1-4

Nathaniel Dusk II (DC): 1-4

Neil Gaiman’s Neverwhere (DC/Vertigo): 1-9
New Gods (Baxter; DC): 1-6
New Mutants (Marvel): 1-100; Annual 1-7; Special Edition 1, Summer Special 1
New Teen Titans (DC): 1-40, Annual 1, 2 (becomes Tales of the Teen Titans)
Nick Fury, Agent of S.H.I.E.L.D. Special Edition (Marvel): 1-2
Nightside (Marvel): 1-4
Otherworld (DC/Vertigo): 1-7
Phantom Stranger (DC; ’87): 1-4
Power Man & Iron Fist (Marvel): 50-125
Rampaging Hulk (Marvel; mag): 1-9
Richard Dragon, Kung Fu Fighter (DC): 1-18
The Ring of Nibelung (DC): 1-4
Rocketeer Adventures (IDW): 1-4
Rocket Raccoon (Marvel): 1-4

Roland: Days of Wrath (Terra Major): 1-4

Roots of the Swamp Thing (DC): 1-5

Rose (Cartoon Books): 1-3

Savage Red Sonja: Queen of the Frozen Wastes (Dynamite): 1-4
Scorpio Rose (Eclipse): 1, 2
Section Zero (Image/Gorilla): 1-3
Severed (Image): 1-7

The Shade (DC): 1-12

The Shadow War of Hawkman (DC): 1-4
Shadows (Image): 1-4
Sherlock Holmes (Dynamite; ’09): 1-5

Sherlock Holmes and the Liverpool Demon (Dynamite): 1-5

S.H.I.E.L.D. (Marvel; ’10): 1-6
Silver Surfer (Marvel/Epic; ’88): 1, 2

Silver Surfer (Marvel; ’11): 1-5

Silver Surfer/Warlock: Resurrection (Marvel): 1-4
Sisterhood of Steel (Marvel/Epic): 1-8

Six from Sirius (Marvel/Epic): 1-4

Six-Gun Gorilla (BOOM!): 1-6

Solomon Kane (Marvel): 1-6
Solomon Kane: Death’s Black Riders (Dark Horse): 1-4
Spellbinders (Marvel): 1-6
Spider-Woman Origin (Marvel): 1-5
The Spirit: The New Adventures (Kitchen Sink): 1-8
Stalker (DC): 1-4
Starfire (DC): 1-8

Star Hunters (DC): 1-7

Starr the Slayer (Marvel Max): 1-4
Starslammers (Bravura/Malibu): 1-4
& Starslammers Special (Dark Horse): 1

Starstruck (Marvel/Epic): 1-6
Star Wars-Agent of the Empire: Iron Eclipse (Dark Horse): 1-5

Star Wars-Agent of Empire: Hard Targets (Dark Horse): 1-5

Star Wars-Dawn of the Jedi: Force Storm (Dark Horse): 0, 1-5

Strange (Marvel; ’10) 1-4
Strange Tales (Marvel; ’87): 1-19
Sword of Sorcery (DC): 1-5

Sword of the Atom (DC): 1-4, Special 1-3

Tales of the Cherokee (Mandalay): 1, 2
The Thanos Imperative (Marvel): Ignition; 1-6; Devastation
Two Gun Kid: The Sunset Riders (Marvel): 1-2
2001: A Space Odyssey (Marvel): 1-10 plus Treasury Edition
Uncanny X-Force (Marvel): 1-5, 5.1, 6-19, 19.1, 20-35
Vertigo Verite: The Unseen Hand (DC/Vertigo): 1-4
Warlord (DC; ’92): 1-6 ( I have 1-104 of the original but missing a handful of issues still from 105-end of series)
Warlord (DC; ’09): 1-16 
War of the Gods (DC): 1-4
Watchmen (DC): 1-12
The Weird (DC): 1-4
Wulf the Barbarian (Atlas/Seaboard): 1-4

Wyrd, the Reluctant Warrior (Slave Labor Graphics): 1-6

X-Men and the Micronauts (Marvel): 1-4
X-Men vs. Agents of Atlas (Marvel): 1-2
Zatanna (DC; ’10): 1-16

a few other long runs (like X-Men 2nd series 1-75) are in my collection as well and they represent all I want of a seires, but not all of the series. 

-M