Micro R/C plane (weight 18 g, wing span 24 cm, powered by 3.7 V 135 mAh LiPo battery) costing just around 25 € all inclusive.
An ingenious design and engineering - all control is non-mechanical, via collective and differential engine thrust. Flies 10-15 minutes per charge.
Made of "indestructible" extruded poly-propylene (EPP) foam. Hard landings are no problem - the real danger is getting out of sight or being caught up on a tall tree ;-)
Specifications, review by David Boddington, appeared in Model Flyer, December 2005
For great indoor fun, check also Silverlit PiccoZ: world's smallest R/C relicopter!
Video clips, review by Julie Strietelmeier, appeared in The Gadgeteer, December 11, 2006