Samsung A670. Had it for about 16 months before the hinge finally gave out and broke (just like my brother's and his ex-girlfriend's).
I'm planning on keeping my Sidekick 3 for two years (until December '08), but I know I'm kidding myself. I don't think it'll last that long. I'll probably have to start using my 3250 until my contract ends, but my SK3 has been holding up pretty well so far; I can see it easily breaking, or the screen snapping off.
nokia 6310i , 6100, and 3310 , all still in daily use by parents , and older members of my family , solid , reliable , battery life excellent , and no probs if dropped or stolen , who would wwnt to pinch them ?