What mouse do you use?

SS Kinzu.

Trust MI-4950r wireless. I like it.

Gigabyte M6900
Pretty cheap for this kind of mice, works well.

Deltaco MS-483 (cheap 10 buck mouse). small as hell

Logitech mx518. 7 years already i think.

Roccat Kone [+]

Logitech LX8. Basic mouse that came with keyboard, no very good, but acceptable.
Since middle button is broken [have remapped sidescrolling to middle button :D]
I finally ordered new one from sale (Performance MX) and waiting for it to arrive :)

Razer Mamba 2012 edition

Logitech G700. Bought it at 400HKD which is roughly 50 US dollars, it's great and worths every penny.

Natec Genesis GX55 http://www.natec-europe.com/MOUSE_NATEC_GENESIS_GX55_GAMING/id1/pidZ13704.html

HP USB 3 Button Optical Mouse

logitech mx518 :)

Razer imperator ME3 collector's edition

Logitech G600

Razer Mamba: http://www.razerzone.com/gaming-mice/razer-mamba

X7 A4tech mouse

Razer Naga !!!

I'm using a Zalman FPS Gun. I used to have wrist pain and finger numbness (maybe mild Carpal Tunnel Syndrome), and due to the different handling and wrist position during its usage, FPS Gun made my wrist a lot better. :)

Genius 310X

Steelseries Sensei!

Natec Genesis v55

This one

Logitech G700

The rodent kind.

Steelseries Xai, best mouse I've ever used.