
The CuckooIP is a student-built, Internet-connected cuckoo clock that receives alarms by phone (call and record a message and set a time for it to play) and then replays them at set times: the cuckoo comes out of his hole and the recorded message plays back. Full source is available on the site.
Link (Warning: Site is all Flash AND it resizes your browser window!)
(via We Make Money Not Art)