I'm surprised it failed that quickly! Was it still under warranty?
I've been using the Logitech Nano series for a number of years with my laptops. This is mouse I'm currently using. It's very similar to the MS Mobile Mouse 4000.
http://www.amazon.com/Logitech-Cordless-Laser-Mouse-Notebooks/dp/B000TKHBDKOtherwise, I've been using the Microsoft Laser Mouse 6000 series which they consider a "gaming mouse". While I do use it for gaming, the majority of the time I'm using it for day to day use at home and work.
Anyone using the Ergonomic Keyboards? I've been using the MS Natural Ergonomic Keyboard 4000 for a couple of years now. I'd give up both of those mice before I give up the keyboard. It's made such a difference for me. My wrists and arms don't hurt all the time anymore!