Ok, so it was 'suggested' there may be some interest in the sign on this mini dio I made for a friend to display his 1/24th models. As such, it is not up to the standards normally shown on here but I used EL wire (electro Luminescent) for the 'neon' sign which I think looks quite effective. Due to the construction of the wire, it is not possible for even this 1.3mm dia. to bend at a sharp 90 degree angle, so I hand painted the lettering onto 1mm plastic sheet then cut around it and glued that to another sheet of 1mm. I then drilled holes where the wire appears and disappears but at an angle so the wire is not forced in a sharp bend to lie 'flat' on the sign. (sorry, I didn't take progress photo's!). I used 2 x 1m lengths of the wire - they come with plugs attached so I threaded the it in and out without bending it too sharp on the back, hence the cut out in the building to allow for the depth of these wires. You can cut them to length easily but as I had around 10" left, I glued this along the inside top of the windows to give a glow to the interior (It's only about 1" deep and drawn with coloured pencils so kept fairly indistinct). This is powered by a 3v battery pack which has 4 positions - off/on/slow flash/fast flash but the company does packs with up to 12v which apparently make it glow brighter! My main problem was gluing the stuff! I tried superglue, both thick and thin and 5 minute epoxy, none of which would hold it, especially as it 'springs' somewhat and plastic cement doesn't touch it. I ended up bending each letter then using a hot glue gun to stick it then before it set fully, cut any excess off with a scalpel, leaving glue just under the wire. I also glued the back where each wire goes in and out to stop movement.
the company I got the bits from was http://myworld.ebay.co.uk/elwirecraft&ssPageName=STRK:MEFSX:SELLERID&_trksid=p3984.m1543.l2533
who had great service, answers questions quickly and has some good tips on the website.