300 (not the movie)

Three Hundred.

A list of mechanics for video games - not ones that have been used, but interesting new ideas. They're published once a day by "squidi" (Sean Howard), along with concept art. A few are sort of derivative and/or uninteresting, but most are pretty good, and some are brilliant. (Notably ideas number 10 and 28.) It's worth a look.

A note on the author - 'squidi' is a nutcase. Because of this, he's a magnet for internet drama - getting into raging arguments with a fellow who used one of his characters as a forum avatar and then with people who criticized him for arguing, etc., etc.. Thankfully, the craziness rarely shows through - it's nearly exclusively contained in 30 - but I felt that fair warning was needed.

That said, investigate! There may be some thing that strikes your fancy.