1. Buy a mount for a Garmin nüvi GPS unit and a hard case for your phone. (There are cheap versions of both on eBay.)
2. Carefully cut away the clip ends on the mount's attachment bracket. This allows you to stick the bracket flush to the back of your phone's hard case.
3. Affix sticky pads to the bracket. Align the bracket on the back of the hard case and attach it firmly.
4. Attach the mount to your dashboard and clip the bracket and case onto it. You can now easily insert and remove your cellphone.
Have an idea for a simple project? Sent it to us at firstname.lastname@example.org
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.