Not much to say that the title already hasn't. Where have you seen really old Macs that are still in use every day? I'll kick the thread off. A few months ago when doing a one-shot voiceover gig, the guy at the front desk of the recording studio I went to was still using one of the original translucent white iBook G3s. It was running OS X, but I didn't look closely enough to see what release. This was in Tokyo, up towards Akihabara.