Playboy made this plugin.
This plugin, as the name says, displays random facts on the XMB. It changes each time you reboot/exit from a game. In order to display the random fact, you'd just have to press both the L and R triggers. (L + R).
Prepare to be blown away by some really cool facts!
How to install this plugin...
You should get a folder named FactXMB once you've unzipped the attachment. Copy the folder, and paste it to the root of your memory stick (ms0:/). Next, edit your vsh.txt (ms0:/seplugins/vsh.txt) and add this line "ms0:/FactXMB/FactXMB.prx" (without the quotes) to it. Enable it in recovery mode, and you're good to go.