I recently picked up a Nokia C3-00 for it's normal price of $90 (no contract). It's 2G, S40 OS but with a UI face lift to make it more like S60 with a very good customizable home screen (I never visit that Nokia grid except to access the settings menu). I've used a number of Nokia's other budget phones and there is a big difference between them and the C3. The C3 has a bright, crisp screen compared to the more washed out screen on most of the budget Nokias. [Edit: However like most of Nokia's phones you can't change the default power saving settings, so the screen will dim and turn off if you leave it idle]. I never figured out what CPU is inside (it's not published anywhere) but whatever it is it is very responsive. It doesn't have the input lag other Nokia budget phones have - even with the MP3/Video player going in the background it remains equally responsive to input, though I do notice that it takes longer to load the web browser. I was also able to load Age of Empires 3 via microSD and it ran full speed despite being designed for higher end S60 devices.
Volume and voice quality is ok but not anything special, if you are hard of hearing this is not a good phone (by comparison the cheapy 2760 is excellent for old people). The qwerty keypad is very good with raised keys and solid keystroke; I've used a number of Blackberries and wouldn't consider it any less. The navigation keys don't have any issues (the end call/power off has less travel/feedback) though I've found the 2 raised shortcut keys (default to contacts and mail) can be accidently pressed by my flip case if the keypad isn't locked. The overall build quality is high - no creaking and the back is some kind of aluminum cover. I think that Nokia managed to do something very smart with the build quality of this phone, avoiding the cheapest construction and using premium parts in a few key areas to make a S40 phone feel like a high end one.
The camera is 2MP but useless - no flash, poor focus, takes the kind of grainy pictures you'd associate with 'cell phone camera'. The built in mail app also likes to resize any image to 640x480, even if you try attaching them as a file instead of a photo. There is no dedicated camera key and if you need a cell phone camera on a regular basis you should look elseswhere. Speaking of buttons there is one major feature omission - no dedicated volume buttons. This is probably the one problem I would want to see fixed. Since the phone doesn't do multitasking you don't have any way to adjust the volume of the MP3 player if you are browsing a webpage - you have to close the browser, change the volume, then reopen the browser and reload the last page (there is a shortcut to do this).
Battery life is excellent, rated about 7 hours of talk time which has so far matched my real world use (though I've never run the battery all the way down - it may be better then advertised). It seems to cope well with poor signal areas, except for the mail app which frequently gives up on slow to respond mail servers. Combined with the strong build quality the size is also good - not too big in any dimension, easy to hold and operate with one hand, good weight (though the vibrate is kind of weak).
So if you want a phone for basic calling, lots of texting, basic web browsing and music listening this is a good deal for a well built phone. If you want Wifi, camera, 3G, an App store or other features don't waste your time, it may advertise some of them, but it doesn't do them very well (The Ovi Store has very little of quality for this phone, you're better off looking for generic S40 and S60 Java applications elseswhere).