An app called installous is good, its basically another installer type thing like App Store, but its loaded to the brim with cracked Apps from the app store.

example: Assassins Creed - £5.99 (App Store), from Installous - FREE!

A few I got that I use regulary: Flashlight (best torch out), xGPS (turn by turn voice navigation), and ofcourse, ICY (faster than Cydia!)