Hello Philippa and Georgina and Jo Jo and Sarah and to others who I can’t remember.

The following are the links I said I would post which are related to your projects:

Charging while walking:
http://www.sciencedaily.com/releases/2007/10/071019183459.htm
http://www.technovelgy.com/ct/Science-Fiction-News.asp?NewsNum=452
It’s worthwhile looking at how this motion produces electricity:

This one involves usual solar power
http://www.abc.net.au/science/news/stories/s1079991.htm

Potato battery
All you need for this one is 500 lb of potato

http://latteier.com/potato/
Not sure if this is possible either – but we can test!
http://uneasysilence.com/archive/2007/01/9276/

Onion and ipod
Looks like this may be a fake, but how can we tell . . .?

(not so) constructive comments:
http://www.fazed.net/view/?http://mailman.cloudnet.com/pipermail/compost/2003-December/011534.html
Heat from Manure
Not too much out there, but at least it seems to have been done before:
http://mailman.cloudnet.com/pipermail/compost/2003-December/011534.html

Good luck, and keep me informed.