Best PS2 Mod?

[FamicomFreak]

I have been looking on sites for the past hour and was wondering what is the best mod out there for PS2? If I don't find anything soon I'll just wait a month when my sister goes to Peru and Mod it there. My brother took the PS2 I use all the time and that was moded....sob I want my moded PS2 so I bought a fat one for 20 bucks from this dude. HELP!!!