Main Good Idea
If you have some free time on your hands, here you go -- some neat tricks on smartphone photography. The idea with a card board made tripod and headphones is neat.
Keyless Entry Using Your Phone:
Something that you see and remember.
Home made wine cellar:
Make sure the mounting brakets and ceiling can support what you are storing, otherwise you'll need some bodywork done on your car.
Everything is powered by USB nowadays, so this seems like the next logical step. USB wall charger, replaces your current one and can support USB 1 - 3. Simple and elegant solution, available for $24.99 from ThinkGeek.