Personally I'd want to do something that's mostly play-by-post with a posting regularity of once-a-day or every-other-day expected from the players. The idea of occasionally meeting up for the larger combats is good too.
As for non play-by-post (either constant sessions via descriptive text like Denga used to do, or the much more rapid and personal Skype sessions as Fazz suggested), I'm not sure if I have the time.
Whether play-by-post or otherwise, as with any potential group, it'd be best to
initially think not so much in terms of campaigns, but in terms of one-shot scenarios. Makes players dropping out easier to accommodate and makes the whole thing less stressful.
As for traditional systems, I am either slightly familiar with or have an interest in:
-Shadowrun 4th Edition
-D&D 4th Edition
-D&D 3.x/Pathfinder if we all agree to be a certain tier or below (I think on the interwebz it's accepted that some classes like Wizard are Tier 1 or God-Tier, while regular old fighters are more along the lines of Tier 3 or average-tier)
-Paranoia
As for non-traditional and/or more silly or free-form oriented systems:
-Primetime Adventures
-Kobolds Ate My Baby!
-Don't Rest Your Head
-Monsters and Other Childish Things
As for potential ideas/settings I'm interested in running or seeing others run(assuming a system with a GM is picked):
-Recently saw Sword Art Online (a terrible anime with a cool premise) and have been wanting to get into .hack//Sign.
Basically the premise would be the characters are all stuck in a virtual reality MMORPG and can't log out. To me the neatest part of this concept is that the characters would be able to openly talk out loud about the system's rules. For example, if we pick D&D, we can talk out loud about hit points. The concept of XP to level up would be universally known... cue religions and serial-killer based on Highlander philosophy, etc. etc.
-Anything like Paranoia, where the players might secretly be working with/against each other.

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I'm interested in participating in anything with you guys though so please chime in.
