I used to use this a lot. Played in Doctors office, trains, planes and hotel rooms. But now not so much. They are still in like new condition. I have listed them on eBay as a fixed price but I am open to offers.
http://www.ebay.com/itm/252491961727?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649