$79.99 "pulls in extra cooled or heated air to problem rooms, replace register with this 3-speed duct booster fan & plug it in. The sensor automatically turns on the register vent fan per your setting, installs flush; just slide it into a floor register opening measuring 6" x 10" or 6" x 12" and plugs into standard outlet. fan can mount to a wall or ceiling register. Includes a remote control for convenient operation anywhere in the room, plus digital display and 6' power cord. "
The areas around windows are great for utilizing extra space for storage. More storage solutions: http://www.bhg.com/decorating/storage/organization-basics/slivers-of-space-storage/?socsrc=bhgpin090313windowstorage=2