USB Power Supply

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.

• 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

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

I think I will base my design on this and this

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

• Sasha