Hey, i thought i'd put it out there, just in case...
Chase, Brian or Lenny, or anyone who's GMing a big campaign,
you're more than welcome to use my big map mat if you like,
just let me know, and i'll get it to you. i've got the pens that
work on it, all i ask is that you keep it in good shape and you
don't let the ink sit on it for too long; as it gets harder and
harder to get out the longer it sits, especially colors like red and
yellow.

Courtesy.