Ocassionally I have customers bring in those inexpensive painted electric violins. They usually seem to have a plastic base with what I guess is a pressure sensitive pickup attached to the base. More Info.
I recentally had a customer bring in a 5 string little better grade of this type of instrument. He wanted to swap out the original pickup with a baggs pickup. At first we were going to just bypass the control and go directly to the jack, but I thought why not use the built in controls and see how it sounds when it's attached to a good quality Baggs pickup.