several apps that i recommend.

petrovich which allows you to send stuff by bluetooth like a normal phone and fMMS which allows you to send MMS messages.

another good functionality app is ukeyboard. adds a pop up keyboard iso you don't.have to use the main key board if you dont't want to.

to use the web browser in portrait mode, press the cntl shift and O button at the same time and it will auto rotate.

i had 25 apps running at the same time last night just to see how it would cope. it was starting to slow down around the 20th app. i don't.think you'll ever need that amount of apps running at any one time but it does show how well it can multitask.