Sonny Ericcson W810! It's great and keep battery very long.
Motorola C118
LG KF600 for about 3 months now
samsung - a crappy one ;)
K610i FTW !
Nokia :) i wont tell you the the serie.. :D
Treo PRO
on Windows Mobile
NOKIA 5310
It serves me whell. But I had to update its firmware 10 times....