I had downloaded a cracked ELF of xploder HD player, stuck it on a usb stick, and started it with my swapmagic. (Only way to start it, as I can't see anything on the monitor before the elf starts up.) I select 480P through the menu of the ELF, and start it up with the swapmagic still inside - and for some reason, it reboots to the ps2 menu. From there, I can go ahead and put in whatever game I want, or play whatever homebrew.
I don't think the PS3 has been hacked yet though, so my method will only work with a ps2.