As already mentioned, telephone wire and 4 and 7 core alarm wire is perfect too.
Often available for nothing as off cuts and often 2 or 3 meter lengths in the skip bin at a builders site.

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There are more ways to get to Rome.

Electricity, Electric clocks, Meters and Trains are great.

Please don't sent me private messages, I will not answer them.
The questions asked can be discussed in the open forums.
http://www.youtube.com/user/RODALCO2007 some interesting electrical stuff to watch.