Wrist watch projects are very popular these days, the freedom of adding whatever feature and look you like i believe is one reason apart the "trend" of smart watches from big companies.
This clock is an evolution from prior ones made by the creator and is a work in progress but still 100% functional and fun to use.
Heart of the clock is a femtoduino - really small Arduino board powered from a 300mAh Lithium Ion battery along with MCP73831 charge controller giving it around 24 hours work time.
Having an OLED screen and programmable "heart" allows for various time display modes including analog like, digital, sentence and even bar graphs, some basic apps like class schedule and even a mini game to kill time.
Head over to the site for more info and pics.