I just bought this Fellowed Micro Trac mouse and all I can say is wow:
http://www.amazon.com/gp/product/B00...824788-7241766
If you have any problems with your wrist being sore this thing is 100% comfortable, its also the nuts with any laptop you want to walk around with. The third button on the top left is actually a mouse wheel as well the only thing is you have to take it off to type but whatever this thing is amazing, enjoy.