Love the genre. But I have, so far, XOP and all of its varieties and sequels, as well as some (pretty awesome) ones like Cho Ren Sha 68k.

Trying to branch out, but its hard work making a good shmup. Where are the free ones?

Fans of gradius should check this out:

http://www.youtube.com/watch?v=lf5NaSPODtg