Kensington Orbit Mouse - Wireless Mobile & Compact Ergonomic TrackBall Mouse for PC, Mac and Windows with Touch Scrolling, Ambidextrous Design and Optical Tracking - Red (K72352EU) : Amazon.co.uk: Computers & Accessories
Kensington Expert Mouse - Wired Ergonomic TrackBall Mouse for PC, Mac and Windows with Scroll Ring, Ambidextrous Design and Optical Tracking - Grey (64325) : Amazon.co.uk: Computers & Accessories
Kensington Expert Mouse - Wireless Ergonomic TrackBall Mouse for PC, Mac and Windows with Ambidextrous Design, Optical Tracking, Scroll Ring & 55 mm Ball – Red (K72359WW) : Amazon.co.uk: Computers & Accessories
Kensington SlimBlade Pro Trackball Review: Fully loaded, but not for beginners - General Discussion Discussions on AppleInsider Forums
Kensington Orbit Mouse - Wireless Mobile & Compact Ergonomic TrackBall Mouse for PC, Mac and Windows with Touch Scrolling, Ambidextrous Design and Optical Tracking - Red (K72352EU) : Amazon.co.uk: Computers & Accessories