An instrument with strings.
Used cycles settings and used the wood material that wesvdes uploaded to blenderartist.org and then just tweaked it a little (which is what you would also do but htis has been UV unwrapped so putting some other texture on it shouldn't be too much of an hassle . Total verts: 83073.
A real wood texture is though much better on this, but I still have not found a proper cello wood to put on it, I guess a trip to the music store with a camera might be the best solution to get the right texture. I tried some wood texture from cgtextures.com but there was nothing quite right there for me.
The front and back need to be curved.
Here are the pics. CC0 (do whatever you want) so you can make the textures.
101mb. http://ompldr.org/vZzJjcg/cellopics-cc0.zip
nice upload.