I just picked one of these up today for my downstairs pc. Microcenter had them on sale, $5 off in store with a $15 mail in rebate. So far, I think it's pretty neat.
http://www.microcenter.com/images/shared/products/0345829_110577.jpg
http://www.microcenter.com/single_product_results.phtml?product_id=0345829
SIIG Wireless Mini Multimedia Trackball Keyboard
Keyboard Color Black
Keyboard Design Ergonomic
Keyboard Layout QWERTY
Number of Keys 81
Connectivity RF Wireless
Interface USB
Wireless Range Up to 33 ft.
Frequency 2.4GHz
Battery Requires 2 AA batteries (Included)
Mouse Specifications
Mouse Type Trackball
Mouse Buttons 3 Buttons
System Requirements
Supported Windows Operating Systems Microsoft Windows 2000, Server 2003 & 2008, XP, Vista, 7
Physical Specifications
Dimensions (WxDxH) 6.4" x 13.6" x 1.9"
What's in the Box
What's in the Box Wireless Mini Multimedia Trackball Keyboard, USB Wireless Receiver, 2 x AA Batteries, User's manual
Manufacturer Warranty
Warranty 3 year limited warranty
Rebate Details$15.00 SIIG mail-in rebate
View and print rebate (PDF)
Starts: 06/06/2011 Ends: 07/03/2011