Dlink AV 500 power lines. Plug one end in by your router and the other end by your smart tv/ computer / games console and get online with a high speed wired connection. Will take £15 for the pair.

http://www.argos.co.uk/m/static/Product/partNumber/1398405.htm?CMPID=GS001&_$ja=cgid:8710716542%7Ctsid:41408%7Ccid:177979742%7Clid:57860464622%7Cnw:g%7Ccrid:38920536902%7Crnd:11292760567436871858%7Cdvc:m%7Cadp:1o1