Amazon.com: LEGO Technic Power Functions Motor Set 8293 Building Kit : Toys & Games
LEGO Power Functions Motor Set 8293 - US
Make Your Own Lego Motor Case and Shaft Adapter : 6 Steps - Instructables
NXT® motor internals
Amazon.com: PHYNEDI Goshfun 20Pcs Motor Power Modification Accessories Building Set for Lego Technic, 2X M-Motors, 4X L-Motors, 2X XL-Motos, 6X Battery Box, 4X Receiver, 2X Remote Control : Toys & Games
Power Functions Electric Motor 8883 8882 88004 M Large Servo Motor For Lego Part | eBay