Been playing this game called heroes of newerth, it's a remake of some older game called dota that I never played before, it's multiplayer only, and something like an RTS where you only control one character, I believe recent release demigod is similar but i haven't tried that either, so...
it's very addictive and fun, its also hectic as hell and requires alot of macroing skills and concentration, if you like RTS style games you will probably like this. It is a steep learning curve as i found out as i've never played anything like it before.
they're on facebook, thats how i got invited, they also have a website with a forum, etc. the download is only about 300mb too.
Anyway it's in beta but its very polished and free and i've got two invites left, so who wants in?