ALL CREDIT GOES TO RED SQUIRREL! :Punk:
This was something i asked from Red Squirrel a while ago for my PSP, because i was tired of hearing my UMD Spin, but i wanted my UMD to be in my PSP for storage and also when i wanted to play my game.
No it will not do any harm, it just shows the tray as empty.
Just install it like any other plugin.
Purpose: Store UMD's in tray without your PSP loading them on startup and making that spinning noise.
EDIT: Wow, i never knew so many people wanted this, i thought it would be great for me. Im happy to see a lot more people need it too :)