You may have already met Gish as an unlockable character in Super Meat Boy... but his signature game is well worth checking out in its own right. It's an insane, stylish and tricky platformer that challenges players to use the gooey protagonist's blobby frame to advantage, with some neat physics and lighting effects making it stand out from the crowd. It's a bit like Globdule, if Amiga fans remember that one.
Direct2Drive are asking for a meagre £1.59 thanks to their KAPOW voucher code, which is £3.50 cheaper than everywhere else. Bargain.