Jeff Minter is lovely.

Gridrunner ++ - a demo version of which featured a level consisting solely of my head sweeping in for attack - featured in Gamer's Top 100 a couple of times before being ejected this year in a moment of whimsy.

This appears to be the full version, with added swearing, a wider-play area and a few other bits and pieces. It's a gleefully intense little shooter, and if you like this you should sincerely consider buying the "normal" version for a fiver.