USB Power Supply

Description
I would like to build a USB Power supply that I can carry around everywhere, to use wherever needed. It has to cope with up to ~10w @ 1 -> 12v.

Goal

 * Make it safe, with short circuit & overload protection
 * It cannot be any bigger than a credit card, and not very tall either
 * Settable to 0.1v and 10ma, and fairly accurate
 * Goes all the way from 1v to 12v, up to 10w in total

Obstacle

 * I have almost no electronic skillz
 * It has to be safe, with beefy diodes protecting my computer

Components
I think I will base my design on this and this

Schedule
None really... preferably 1 or 2 months from start to finish though

Participant

 * Sasha