What are you looking to do with it? You basically need cydia installed before you can do anything really cool.
Lockinfo is pretty tight, it changes the lock screen to where you can have widgets / rss feeds on there.
Winterboard lets you customize the background, dock, etc...
I made my dock 5 icons wide, use lockinfo to display weather, push notifications, texts, etc, and I use winterboard to make all my icons transparent.
So what exactly do you want to do with it? Im not a gamer really but i know you can put NES, SNES games, etc on it.