Regarding felt marker ink on keytops -- there is a technique mentioned in the August 2012 Issue of the PTG Journal, page 10.. Harry Buyce, in 2004, suggested the following: "I have discovered a process that will remove the marker ink and will not damage the plastic keys. It is called Aero Brand #1250 Ink Reactivator, manufactured by Specialty Ink Co., Deer Park, NY. You can find this product at a large rubber stamp company that wholesales to other dealers, or find it online. You wet a cloth with this solution and wipe the key. The black will just disappear... I have not tried it but if it works, it would be much easier than the methods recently put forward on the list. Jim McCormac RPT, San Diego