Make a ghost detector.

This video is of the complete assembly of an electrostatic field ghost detector that uses a common cheap TV antenna widely available from dollar store type shops. I got mine from Poundland.
It uses a super high gain Darlington array of common NPN transistors with the input biased very slightly to make it more sensitive.
I designed this for a friend who does a lot of ghost hunts. You can see his website at www.walkingwithghosts.com
The two antennas give a good responsiveness to ambient electrical fields.
In this design I used BC547 transistors because they are pretty much the standard NPN transistor used by geeks in the UK. You should be able to substitute different transistors although their base, collector and emitter pins may be different.
The use of a reverse biased red LED to give a tiny bias current may seem a bit odd, but it gave the best results in my experimentation.