what are some cool electronic things you can make?

Question

i just want something that does something cool and is easy to make perferably using pic microcontrollers

Answer 1

I once built a circuit that would blow an airhorn when the main horn had been on for 1/2 second. ~
Thus short honks only sounded the factory horn, but if someone didn't mind that, staying on the horn button solid made the airhorn kick in. Had them jump out of their seats.

Answer 2

Check out this website

http://www.robotstore.com/ or even this other site: http://www.solarbotics.net/library/circuits/bot_walker.html
or even one more very cool site:
http://www.amazing1.com/