I do run a regular game (of some sort of RPG) just about every weekend, but I do collect and read a lot more RPGs than I play. I'm definitely an "armchair RPGer" of certain systems, such as Rifts (played the TMNT game, and when we beat Shredder with 1st level characters, [and after playing a year of the Robotech game] decided the system wasn't to my liking - though the fiction was interesting).
I also tend to raid other books for ideas and whatnot, usually adventures. I don't like mixing and matching systems, but I have sometimes found things worth pulling into other games.
[edit] I also find myself getting frustrated at RPGs. I'm a story person and when things tend to go sideways in the game, I become somewhat irate - especially when bad mechanics (or, more often power gaming) stomp all over good story elements.
Games for the curious:
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Regularly Play(ed): Aliens (my own RPG), D&D BECM/1E/2E/3E, Serenity, Vampire, L5R (3E), Star Wars d6, Gamma World (2E?), James Bond, Robotech, Star Trek (Last Unicorn), Villians & Vigilantes, Marvel Superheroes
Tried (Read, generated characters and at least one adventure): 7th Sea, Alternity, Castles & Crusades, Chronicles of Ramlar, d20 Modern, DC Superheroes, Deadlands, D&D 4E, OD&D, Farscape d20, Hunter, L5R (1E), MERP, Pathfinder, Pendragon, Rolemaster, Shadowrun (2E), Star Wars d20, SWSE, Star Frontiers, Spycraft (1.0), Mechwarrior, Star Trek (FASA), TMNT, Toon, Werewolf
Have, but not yet played: Burning Sands, Call of Cthulhu, Dark Heresy, Fading Suns, Fireborn, Three-Sixteen, GURPS, Mouse Guard, Mutants & Masterminds, Space 1889, Stargate SG1 d20, Twilight 2000, Warhammer Fantasy RP (2E & 3E), Weird War II, Wraith
Have, but will not play: L5R (2E), Rifts, Stormbringer
There's probably more, but I can't think of them now...
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