MrMunki has a good Instructable on making a super-compact 9 volt USB charger, he calls it a YAN9VUSBC (Yet another 9 volt USB charger) and besides its small form factor, the name is why I really like it – Link.


  • MintyBoost! – Small battery-powered USB charger – Link.
  • 9V USB Charger Kit – Link.
  • Tons of USB charging action – Link.