Serial over Cat5/Cat6 RS232 Extender, Up to 3280 ft. (999.74 m) | Eaton
VGA & RS232 Extender Over 2 CAT5 Cables -Perfect for Touch Screen Applications | eBay
Gefen RS-232 Over Cat 5 Extender
Tripp Lite HDMI + IR + Serial RS232 over Cat5 Cat6 Active Video Extender TAA GSA - video/audio/infrared/serial extender - B126-1A1SR - Audio & Video Cables - CDW.com