You may be interested in the Pocket CHIP, it's pretty much what you asked for minus the sleek case, and I don't think the battery lasts quite that long (but it'

You may be interested in the Pocket CHIP, it's pretty much what you asked for minus the sleek case, and I don't think the battery lasts quite that long (but it's open source and hackable so you can add your own if you want): https://getchip.com/pages/pocketchip https://getchip.com/pages/pocketchip