As written in the N in-game help: "It won't stop weapons, but it's kinda fun to jump on." Bounceblocks are those white blocks hanging around. They won't stop enemies, won't block shots, won't divert anything, but they are solid and you can't walk through them (sadly). They wobble when you touch them, which is where the "bounce" part comes in. For some serious air on these things, the key is to wait until the bounceblock goes all the way down, and when comes back up, jump. You should go fairly high into the air. * 74-4: Zenith