For the record, there is a mute you can buy that will silence your violin quite cheaply and effectively: The Tonwolf Violin Practice Mute.

Problem is, if you play heavy, as I do, they have a habit of leaping off the bridge and landing on your toe (if, like me, you're a bare-foot fidder) which can be extemely painful as these things are very heavy. I've also smashed several items of crockery with them. Those heavy rubber mutes aren't so good at silencing a violin - I use one as a matter of course and can readily complete with banjo & concertina. As with horns, Mutes are generally more about tone than volume, though I've yet to find one that'll give my fiddle the Harmon buzz, like Miles Davis, though feel it's not beyond the realms of possibility.

Some very interesting electric violins from Song in China on ebay right now (see HERE. I'm thinking about getting one for my birthday for similar neighbourly reasons. Richard's right though, anything like this will need all manner of setting up and tweaking before it's playable, but this is half the fun. I bought a weird looking Song Baroque 5-string a couple of years back and love it very dearly; nice instruments if you get them at the right price - though they regularly crop up in UK dealers a lot more than you can get them from Song.

Another option of course is the practise violin itself. There's one at Pamela's Music just now: 19th Century Frame Fiddle. You can easily make these electric, as Ric Sanders did with his.