A real gem... particularly if you, like me, run 'cod-archaeology' adventures in which hidden secrets lead to high adventure.
This image - in full colour and greyscale versions - hints at all manner of hidden knowledge with wierd symbols that are tantalisingly like letters, if only you happened to know the script.
If you are running a contemporary or future game, heck, even a fantasy one, there's bound to be somewhere suitable for this: a wizard might have it on his door, it's found at a dig site or on a strange alien space station...
The possibilities are endless, and it looks good too!
The licence is straightforward if written in a rather pompous style, my only complaint is that the text is not available before you make your purchase - a minor nit-pick as you can do most anything with it (except put it in a collection of art for resale) provided you give the artist a credit.