I can almost hear the james bond theme, and see a man walking in front of that hole, turning and drawing a gun....fade to red.

Yep, I've seen alot of these in the smithsonian exhibits, they usually record temperature, humidity and something else.... there is a red green and blue inkblot on there. Don't know what the third one measures, pressure?

It's a shame I dont live nearby... as a locksmith I could get him into every room in the complex very easily. If you ever know any places near tampa florida, let me know I'll let you in where ever if you give some credit! :-p