Suggestions on choosing a "technology"

I'm supposed to research on a technology that uses any or all of the magnetic, gravitational, and electric fields. Any ideas about an exciting technology that matches this criteria (eg: MRI machines)?

Perhaps something that will make the artificial appendix obsolete.

Compass Compass Compass!! It uses the magnetic field, and it's really... complicated.... if... ... ... ... ... ... ... you... ... ... lose it?

Gravity... hmm what uses gravity... let's see.. cars, me, tables, desks and *everything* else in the universe!

Thanks...now I have to present it in a non-conventional way. What would a good method? A webpage? A game simulation (can you explain that please)? A flash movie?

Hey, could you use osmosis to power a generator? (if you had a thing.. onyl water cold pass through.. does it drip back, and move into the other side????)

Hmmm, use a compass to hack into a computer, who says it's no possible??