CORSAIR Katar Pro XT gaming mouse weighs 73g with 18,000 DPI sensor at $25 (Amazon low)
Corsair KATAR PRO XT Review - RTINGS.com
Mouse Gaming Corsair KATAR PRO XT - PC Garage
I want to bring more attention to this mouse (Corsair Katar Pro XT), as I think its an absolutely great budget option that flew under most people's radar - More info in
Corsair Katar Pro XT - closed gaming mouse weighing 73 grams in test