I saw someone turn an iMac into a fishbowl, that was pretty sweet. I guess the only use I could think of for one of those now....
Oh, goodness no. Stick Panther on them and they'll run great! Also, his seems to be a Graphite, which means it's at least 450MHz, if I recall. It's one of the nicer iMac G3s you'll find.
Hold onto it and use it as a jukebox in an area of the house where you wouldn't normally put a computer!