I tried 9 different trackball mice — here's how to find the best one for you | Tom's Guide
Logitech MX ERGO - Trackball - optical - 8 buttons - wireless - Bluetooth, 2.4 GHz - USB wireless receiver - Hunt Office UK
Orbit Trackball Mouse - Osmond Ergonomics
YUMQUA Portable Finger Hand Held 4D Usb Mini Trackball Mouse/Fits Left and Right Handed Users Great for Carpal Tunnel Laptop Lovers : Amazon.co.uk: Computers & Accessories