I bought my 3400 brand new in 1997 and I still use it 2-3 times a week today, mainly for IRC chatting or checking email while watching TV. It's running OS 8.6 because 9 feels like a resource hog on it, so browsing can be limited. It still has the original battery, which still holds a charge for WELL over a week in sleep mode.

If you're wanting to do some surfing, watch YouTube, etc., then anything older than a G3 is not for you. Even with OS 9, your browser choices are pretty limited and time will only make that more of a problem. I recommend getting a Pismo and putting OS X on it.