Logitech MX ERGO PLUS Advanced Wireless Trackball Mouse Black 910 005178 - Office Depot
Logitech ERGO M575 Wireless Trackball Mouse - Easy thumb control, precision and smooth tracking, ergonomic comfort design, for Windows, PC and Mac with Bluetooth and USB capabilities - Graphite - Newegg.com
Hands-on with the new $50 Logitech Ergo M575 Wireless Trackball - CNET