Taskbar Notifier brings mail and SMS received icons to, you guessed it, the taskbar. With it you can see if you have messages waiting without unlocking the screen. Very handy, as 99.9% of all other cell manufacturers had already figured out by around 1998.
You may get a better response in the apps and hacks sub forum. This forum is full of iSheep and Fanboys that feel you should only be useing the phone as Apple has told you to, and not as you would like to.
My favorite is checking the installer app, and waiting to hear that little chime tellimg me I have updates!