The best games that I have found are made by a programmer named Soneso.
His website is: http://www.soneso.com/Site/start.html
and the installer source is: http://www.soneso.com/iphone
His games have kept me occupied for hours, I would also suggest iSolitare, Pool, iPhysics, and Tris, all of which can be found with the Community Sources installed!
Enjoy I love the iPhone when it is hacked!
Mobile Chat - Simple, easy to use IM client with support for AIM, .Mac, Gtalk, MSN and ICQ
Tris - A tetris clone. Tetris was like made for multitouch 😛
Touchpad - an app that connects to your computer using VNC, you can use it as a track pad, keyboard, or remote. I mainly use it to control front row, since the default apple remote is a pain to use IMO
What source must be installed for this app?
i'm really obsessed with iZoo which is basically Bewjeweled...
SwapTunes is a great app for syncing up to other iTunes libraries without losing your own files
Get Summerboard to change your themes and wallpapers, as well as Customize for other customization needs
Also, get the Flashlight app because you never know when you'll be left in the dark
Flashlight is definitely one of the more useful apps I've found.
The Dock and Poof combo is probably my favorite. Being a minimalist, I like having all of my icons hidden so I can enjoy the high quality of the screen with some good wallpaper.
If they are hidden, how do you access them?
MooCowMusic Apps are all must have apps!!
Websites in my signature and should be able to install all of them with community sources,
Pianist - piano simulator
Drummer - drum machine simluator / sampler
Guitarist - guitar simulator