I found four cool homebrew games I thought I would share with you all.
Block dude by Cools
this is somewhat a puzzle game as you have to figure out how to reach the door by moving various blocks hindering your path. According to cools, he tried to make this game as close as possible to the calc one created by Brandon Sterner. Block Dude v0.2 comes with all the original 11 levels and there are three extras from the flash remake. The developer added that a handful of custom made levels made by Access_Denied, Beefland, and Spirit Hawk have been included as well.
Download Source AOTM (Attack of the Mutants) by DeNitro 
Attack of the Mutants, "nicely polished space shooter with weapon upgrades and much more"
Download Source KETM by Deniska 
PSP adoptation of KETM (studio-grey/badblocks), fast paced tyrian style 2D shooter. Featuring - 4 levels with different environments, music & bosses - 1 bonus level - 15 enemies with unique attack patterns and adjusting hostility - 7 primary weapons - 4 secondary weapons (rockets, laser, bomb, rotating shield) - 2 mods
Download Source Callisto by Weak , Pimpot , Markospex , Klesk 
Very stylish shoot-em-up.
Notes for this version: This newest version has had changes. Callisto v0.2 shows a new planet to raid, and with that comes new enemies and weapons to fight them with. There will also be new power-ups and new bullet and enemy patterns.
Download Source Official Site