Don't know whether everyone who reads this listserver reads the Groundspeak forums, so I thought I'd pass this on, as it's something that's come up here before.
 
A while back Rob from Team CHUMP posted an icon to add to a cache page for handicapped-accessibility. Someone else has taken the concept at little further. See: http://www.syphon.com/personal/scott/icons/.
 
Then, in a response to the thread where I saw this, Jeremy posted the following:
 
After finishing the advanced search feature, palmable data and extension of the log description field, I'll be adding attributes for cache pages (that are voluntary).

Jeremy Irish
 
Steve
Team Tierra Buena