I think I shall make a new instrument

[The Dong]

I don't know when, but costs should be about £60 or so and some weeks of 
careful work:

http://www.youtube.com/watch?v=Ywu1DeqXTg4&feature=related

Ooops, sorry that's the wrong link ;)
This is probably the most famous clip of the instrument, about 1:35 in:

http://www.youtube.com/watch?v=eTsKEgUJyUQ

Generally called a Guqin, not a very common instrument, nor so easy to 
get exact info on, but hey, it's based on harmonics/pentatonic and is a 
fretless instrument. Difficult to find well recorded stuff, here's some 
not so good sound, but:

http://v.youku.com/v_show/id_XNTA5ODY1Mg==.html
http://www.youtube.com/watch?v=fKNeParT2eQ&feature=related

Worth building? :)