1: Mario: What can I say? He's gaming's lead man; going boldly where no other characters dare to. While his games differ wildly in quality it's hard to argue that he isn't afraid to try new things. His two-dimensional nature may be a detriment to many, but that only allows me simple joy in a gaming world that's become very complex. My affair with gaming started because of him and I will never forget all of the amazing times his games have given me.
2: Samus: Pre-Other M, of course. Before that trainwreck sidelined her she was the most powerful female in gaming, unrelenting and beautiful without overtly flaunting it, doing better what her descendants would later try to do, such as Lara Croft.
3: JC Denton: While ol' JC may not have been the most developed character himself, his gameplay opened me to a world where CHOICE mattered. At the time this concept was utterly alien, but Denton and the world of Deus Ex eased me in like no other game could.
4: Planescape: Torment's entire cast: Dark and interlaced unlike any other game, each character is truly something amazing.
5: Link: Zelda's gateway character. Exceedingly simple on his own, it's the universe of characters that attract to him that make him strong and without the quiet elf in place, none of the magic would happen. As ingratiated a player-experience character can be.
6: James Sunderland: Silent Hill 2's hero, his mindset allows to see spectacular horrors throughout and his bizarre nonlinear development is awesome.
7: Durandal: Yes, I have a thing for mad AIs, but I give Marathon's Durandal the edge in this engagement. His banter is witty and helpful, and the scope of his plans are more immediately far-reaching than SHODAN's.
8: The Arbiter: Halo's best developed and most tortured character, he represents a side of the story Bungie had the balls to expose. His character reflects well on the species he represents in the fiction.
9: HK-47: Misanthropic droid from Star Wars: KOTOR, but charmingly human at times. A great representative of BioWare's writing strengths.
10: Frog: From Chrono Trigger. Whilst a tad generic, his heroic overtones and tragic curse were among the earliest I encountered and he became one of my favorite RPG characters in my youth.
11: Eddie Riggs and Ophelia: Though Brutal Legend isn't everyone's favorite game, Eddie Riggs was great, with a fascinating backstory, well-written lines and Jack Black as his voice. Ophelia acts as a perfect counterpart and love interest as a more forward character with a dark bloodline. Jennifer Hale played her role perfectly.
12: Harold: Harold represents the entirety of the Fallout series: mutated, hilarious, dark and very weird. It's hard not to get behind such a character, despite his failing mind and mutated appearance.
13: Abe: Oddworld's mascot character, simple and chipper despite his people's awful state.
14: SHODAN: Evil and freaky AI from System Shock 2 that doesn't take anything from any fleshy human or other organic.
15: Pac-Man: Among the earliest of actual video-game characters, Pac-Man set up the earliest basis of Mario's first innovation: three part storytelling in games.
16: Wario: Mario's greedy, manipulative and ultra-strong counterpart, his golden days were some of the finest available in portable gaming. I still hope for a return to form for fatso in yellow.
17: Guybrush Threepwood: Hilarious Monkey Island character from the golden days of adventure titles. Insult-based combat? Yes please.
18: GLaDOS: Portal's villainous AI is the first of several machines on my list and the youngest of them all, but she deserves her place. Her twisted nature is unnerving, comforting and hilarious. Portal wouldn't be the same without her.
19: Andrew Ryan: Wholly idealistic despite his vast intelligence, his mind powered the rise and fall of Rapture. While I often felt BioShock was a disappointment on the gameplay level, Ryan and Rapture were beautifully depicted.
20: Susano: Okami's best and earliest example of deft character development. What is truly remarkable about this character's rise from fearfulness to heroism is that you're in direct control of his "power" right until he actually gains it himself. Subtle and powerful when it actually plays out.
21: Duke Nukem: Machismo-laced, offensive and womanizing, he's a bit like Travis Touchdown. However, unlike Mr. Touchdown, Duke is the king of his own world, the best of the best. Greatest ego-boosting character ever.
22: HUNK: Resident Evil's staple secret character. His name stands for Human Unit Never Killed, and his other name is Mr. Death. As is said during one of RE3's endings: "THE DEATH CANNOT DIE."
23: Wrex: Mass Effect's brutish, yet honorable Krogan. He is far older than the rest of the cast and acts as a violent backbone to any party willing to use him. His past is tragic, his future bleak, yet even in ME2 he remains steadfast in his goal to unite his people.
24: Travis Touchdown: A brash, immature douche of an otaku with a cool get-up and a cool sword from No More Heroes. His main goal in the first game is violence and getting it on. To me, he's a microcosm for the dudebros of the gaming populace, except cooler. And funnier.
25: Nemesis: One of the most intimidating hunters of would-be horror survivalists in gaming. Resident Evil 3.
Hard for me to organize them on this scale, but that's a rough list of those on my mind most of the time.
You are reading this text. You might stop sometime, but you are reading it now. You now realize that you have manual control of your blinking and tongue. You may now stop reading. Unless you want to keep going. In which case, I love you. Take me now.