Well I'm sure you've all seen teh GreenLee little dart thrower with the string attached to it..... Before it was available I took my pistol grip cross bow and made my own dart/string thrower. It is deadly accurate at every distance I've neede to use it for.

We have used remote control cars to go both under crawl spaces(wireless cameras are awesome for this) as well as accross the top of drop ceilings.

A baseball with a screw in eyelet in it so we can attach a pull/throw string to it.

My son, He was the only one who could fit in the hole.

Let me think of a few more.

Robbie S