Mike Haggar has released a clone of the SFCave game, heres what he says:
SFCave Clone for the PSP. Made in LUA, Partially based on YASFCave. You can play module music files in this game. The music browser starts with folder ms0:/PSP/MUSIC/
You'll need LUA 0.7b7 or better to run this game. The script is a uncommented mess, but take a look if you want to. Feel free to send me improvements if you make some.