Continuous Rotation Servo [FeeTech FS5103R] : ID 154 : $11.95 : Adafruit Industries, Unique & fun DIY electronics and kits
360 Degree Continuous Rotation Servo Motor, DS04-NFC Servos DC Geared Motor, Rust-Proof, Durable and Practical, for Model Aircraft Cars Robots : Amazon.ca: Toys & Games
Micro 360 Degree Continuous Rotation Servo
Continuous rotation servo | Creative Technologies
360 Degree Continuous Rotation Servo, Standard Size