Best phone I ever had was an old 30 dollar Nokia, it was like the first one they made that had a color screen. It had absolutely no features but it always had strong signal and the battery lasted for over a week on a single charge. I still switch my sim card into that one when I go riding, it's tough as hell. One ride we went on I put it in the box in the back of my buddy's suzuki 4x4, and it bounced around in there all day over rocky trails. I open the box to get my phone at the end of the day and it's sitting in an inch of muddy water. Dried it out and it still works fine to this day. That one also slid across my car's dash, flew out the window, slid across the intersection and slammed into the curb once when I whipped through an intersection at 40 mph and it didn't have any damage except road rash.
My regular phone is a Samsung a707 which has a ton of awesome features, but it has it's shortcomings as well. On the good side it has internet with opera mobile browser, mp3 player, 2 megapixel cam, and a big high res screen. On the downside, the battery barely lasts a full day if I use it a lot, the signal isn't as strong as the ol nokia, and the durability is questionable. My brother completely broke his, and the exterior display on mine is shattered from I don't even know what.
But yeah, cheap nokias ftw