"I can't believe I *didn't* want to upgrade. :)"4.0 starson by tanikwish
Pros: Painfully simple, has that tiny cool factor, takes a beating and works fine
Cons: No color screen, messaging can be limited, games were awful
Summary: I had this phone for two years, and upgraded to a much fancier Nokia, and actually miss it a lot. It has everything you want if you just want to chat by phone or SMS -- had many an interesting messaging conversation. It's even Yahoo! IM capable.
It's so tiny, which could make it easy to lose, but it fit comfortably in my pocket and had great sound quality. I got so many great compliments over the phone's smallness. People didn't believe it worked great, but it did and for quite a long time. The buttons were tiny, but are easy to press.
I do enjoy having a mult-color phone with polyphonic ring tones and more difficult games, but that's just a bonus. I had both a Siemens A56 and a Kyocera KX414, a much more expensive phone, and I had a ton of problems with the Kyocera, including freezing a OS. I guess simpler can be better.
If you want a basic phone that works great, even when dropped by me many many times, it's the best choice you could possibly make.