I used to be a moderator on both the Gaming forums Fatalx.net which consisted of around 10,000 members and Runelyfe, but both of these closed due to not having enough income to keep their servers running.
Nope. I have been admin/mod on various small gaming sites, but never anything big =\
Nope i never moderated any big sites.
I've only moderated the forum for my CyberNations alliance. I've administrated my own forums, though.
I have moderated a games forum (no link)
I've moderated
www.punkhack.com a few years ago (at the start of my programming carrier) like 1/2 years. It had 2k+ members.