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You can probably get some kind of USB tuner for it and turn it into a TV, but I bet it'll be too slow to give you much joy as a media server.

Perhaps load a screen saver that points to a directory of photos and make it a large, eclectic picture frame? Or head over to http://www.macintoshgarden.org/ and play vintage games on it.
 
eMacs are a good secondary computer for internet and email. They are no good for video and are a bit to fast for vintage gaming. If you have room, they would be a good recipe computer for the kitchen or in the basement as an email server.
 
eMacs are a good secondary computer for internet and email. They are no good for video and are a bit to fast for vintage gaming. If you have room, they would be a good recipe computer for the kitchen or in the basement as an email server.

Actually, if your just doing SD video, then most eMacs will cope just fine - I can watch SD and DVDs on my 700Mhz eMac just fine, even if I dont use it for heavy lifting
 
eMacs are still great for kids--very good for Mac OS 9 CD-ROM edu games and basic web sites. Not very good for Flash-based sites like Club Penguin though. Maybe you know someone with a 5-9 year old who would get some good use out of it? If it has a DVD drive then it even doubles as a TV/DVD combo.

Other ideas: iTunes jukebox, dedicated bittorrent download machine, run folding@home or SETI.
 
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