Elecom has released 1.4mm (0.06") thick CAT5 cable, which can support gigabit speeds. The cable is so thin that you could run it anywhere, under carpets, (sliding) doors, anything you can think of. The cable is rated for outdoor use as well (and is water proof of course), so this is a great way of providing network access when you don't have the option of drilling holes.
Pricing (connectors included):
D-VAPF/BK10 (10m/33ft): around $34
LD-VAPF/BK20 (20m/66ft): around $57
LD-VAPF/BK30 (30m/98ft): around $81
Just the cable:
LD-VAPF/BK100 (100m/328ft): around $229
Pricing (connectors included):
D-VAPF/BK10 (10m/33ft): around $34
LD-VAPF/BK20 (20m/66ft): around $57
LD-VAPF/BK30 (30m/98ft): around $81
Just the cable:
LD-VAPF/BK100 (100m/328ft): around $229