Here is something that should get the creative juices going. String Jacks can be placed under any number of strings anywhere on the neck to allow the equivalent of bending behind the nut, Koto-type sounds, and other effects. Rich Eberlen sells them for a reasonable $28 on his site where he also shows how he makes very cool music with them.
Great! Simple, refreshing, and beautifully demo’d. I’m going down to the basement workshop and make me up a bunch. But if you can’t DIY ’em, buy ’em from Rich.