The ARC Plasma speaker relies not on electromagnets but an arc of electrical plasma to produce sound.
Sure, you could get a regular old speaker, but it wouldn't have the mad science cool of the ARC Plasma Speaker. Currently seeking funding on Kickstarter, the ARC Plasma Speaker manages to produce sound with pure electricity.
More specifically, a 30,000-volt arc of plasma. The plasma itself can be modulated to generate audio: it charges the air around it, then expands and contracts rapidly at the precise audio frequencies required to play music.
"Your typical speaker uses an electromagnet to vibrate small drums, but a plasma speaker uses an electrical arc to ionise and compress the air around it to play music, all with no moving parts!" creator David Stoyanov explained.
The speaker itself comes with a standard audio jack, so you can use it with your PC, MP3 player or smartphone, and uses a laptop power supply, which you'll need to provide yourself (but will be pretty easy to obtain). All in all, it sounds like a pretty cool little piece of kit, even if the tones are a bit on the fuzzy side.
You can reserve an ARC Plasma Speaker for a minimum pledge of US$99 (plus US$30 shipping) for the build-it-yourself kit, or US$119 for the assembled speaker. Head over to the Kickstarter page for more info.