Pocketwit is this really cool twiter app for windows mobile, more on it in my previous post. One of the awesome features is the built in UI skin/theme customizer.
Heres the one i just created (took like a minute):
All you have to do is go to the "settings" screen(see pic above)
then go to the "UI settings" screen where you can choose from a few existing themes,
pic one that remotely fits your needs and then hit the little "edit" link next to it
use an app like gimp to figure out the gradient colours and other colours and their correzponding RGB values and key them into your phone
thats it, when your done click accept and it will ask if you want to save this as a new theme or not. do what you like and the theme gets applied.