This site has loads of these - but they're also linked to a huge variety of other sites - the ones I've just played with are to do with Unit 4 (quelle surprise!)
However I also looked at robots - to link with U2 and then of course there will be something about inventions too....
Hope you enjoy it too :)
Sange
This is a test on my part, to see if I cana do this!?!?!? Also chose to share this powerpoint, found under advanced search option in google. This has helped us to find suitable info about other materials too; especially plastics :)
http://www.youtube.com/watch?v=D_i3PJIYtuY&feature=related