On trading floors, reception area, command centres, hotels there is often the need to remotely place a large display screen for user/public viewing. HDMI is increasingly used to convey the image signal. Such cable costs about $2 a foot ($5 metre approx) and often has to be retro fitted. I've come across a handy converter adaptor pair which will run HDMI for 100 ft over existing a pair of UTP CAT5e or 150 ft over CAT6 LAN cables.
For greater distances there is a similar adapter pair which will run HDMI across a single multimode optical fibre for up to 305 metres. Great for avoidance of power ground loops. This option also supports remote control.