This Odd-Looking DIY Keyboard Features a Built-In Trackball - Hackster.io
Custom Build] "The Space Between You and Me", a split ortholinear 3x5 keyboard with 4 thumb keys, a trackball, and a rotary encoder. : r/MechanicalKeyboards
Ergonomic split keyboards with integrated trackballs? : r/ErgoMechKeyboards
Amazon.com: Ergonomic Keyboard, 2 in 1 Wireless Computer Keyboard and Trackball Mouse Combo Design with Wrist Rest, Split Keyboard, USB Keyboard for Windows/Mac/Laptop/Computer/PC-Black : Electronics
GitHub - atulloh/oddball: A split keyboard with trackball support
Trackball companion for split keyboards
Adesso WKB-3150UB - Wireless Ergonomic Keyboard with Built-in Removable Trackball and Scroll Wheel, Split Key, Long Battery Life, Small and Portable -Compatible for Laptop/Desktop/PC/Windows XP/7/8/10 : Amazon.ca: Electronics
The 3 Best Ergonomic Keyboard for 2023 | Reviews by Wirecutter