Super Metroid? Me too. So I decided to make a game like it.
Neat thing about Gentrieve is all of the maps are automatically and uniquely generated for each game you play. You can play a short, medium or long game -- or even customize your own game with only the items you like.
Many of the Metroid favorites made it into Gentrieve, like morph balls, secret rooms, boss battles, missiles and double jumps. Gentrieve adds a few more tricks like shields, grappling hooks that can connect to any surface and grenades.
Oh yeah, Gentrieve is completely free. So I hope you enjoy it... if not, you didn't pay anything for it. :-)