Has anyone seen or tried this gadget? http://www.neuserbasses.com/nfs.html The website is not all that enlightening...the PDF that's available there is more informative. http://www.neuserbasses.com/nfs_pdf.pdf Apparently it's an individual-string type bridge (i.e. one bridge unit for each string...you install five of them for a five-string bass) that has some sort of mechanism inside it. You slide the cover and it alters the sound, simulating a fretless. The sound clip on the site is fairly convincing. I'm guessing that what it does is allow the string to vibrate across the bridge fulcrum point when engaged, sort of sitar-like. Allparts carries them. No way will this ever sound like a real fretless, but it does sound pretty cool (at least the clip sounds cool). I do play fretless somewhat, but only on a few songs...the idea of not having to switch instruments (and carry an extra bass) is appealing.