I still have a really old Sony Ericsson that I've had for around four years now, that can only do very limited basic stuff online (that I never use) and is only good for calls and texts. I just don't see any point in going out and getting something like an iPhone or a Blackberry when I only use my phone for calls and texts, and this one has served me well for ages (no matter how many times I've dropped it, it still works perfectly well).
I have the latest iPod Touch anyway, that basically does everything an iPhone would do aside from the actual 'phone' parts, which my actual phone covers anyway, so there's no problem. The only downside I can think of is very limited Wifi coverage since you have to pay for minutes for most of the 'free' Wifi hotspots in my city, I only get free Wifi at university or home, though that doesn't bother me so much...