We have seen watches with built in memory with MP3 capabilities earlier here is the PowerDisk MP3 Player Watch with Bluetooth connectivity. So you can hook up wireless headsets on the go. It is available in capacities ranging from 128MB to 1GB with support for MP3 and WMA files. It is powered by a removable Lithium Polymer battery but how much will it last with the Bluetooth on ?

No word on pricing and availability yet.
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