We've tested it with the following
Dell Laser Printer (1720dn), Apple iPod 30GB, USB to FireWire Adapter, USB 2.0 Thumb Drive (SanDisk Cruzer Micro 2GB), misc keyboards, mice, USB Hubs, a ZyXEL VOIP phone, Bluetooth adapter (generic), etc.  The list could go on and on, but you get the picture.  We recommend using it with any USB device, such as scanners and bus powered hard drives, wide format scanners, and any other high power devices.

Works great with interactive white boards
We've found that AV installers can easily pull it through conduit and install it into classrooms for AV equipment, including interactive white boards such as the SmartBoard.  Being 'daisychainable' you can put two together, and still get the full USB power at the end of the run by powering the USB 2.0 Hub.

Works with all speeds
Some extenders using Cat 5 or Fiber can limit the speed of USB device that can be used (low speed 1.5Mbps such as keyboards, full speed such as cameras 12Mbps, and hi-speed such as hard drives and almost all newer items 480Mbps).  This long USB 2.0 Extension works with all of them.