Phil Terrone writes in with a great weekend project:
Hardware hacker "Ladyada" has released an open source retro arcade style table tennis for two clock called the MONOCHRON. According to MONCHRON project page they "wanted to make a clock that was ultra-hackable, from adding a separate battery-backed RTC to designing the enclosure so you could program the clock once its assembled." It includes a ATmega328 processor (with'Arduino' stk500 bootloader for easy hacking). It's completely open source hardware, all firmware, layout and CAD files are yours to mess with.
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