I know my IP at home changes every time the power goes off.
How often would you want to be notified? Every page-refresh might be a little excessive
I was thinking about something along the lines of the 'who was here' extension, only perhaps with pre-selected IP's being logged. Not shown on the board of course, otherwise our cover is blown.
I'll tell everybody why I was curious about it: over the years we've had a couple of groups splinter off and form new boards, etc, and there are some semi-friendly rivalries going on. I just thought it would be fun to let our inner circle know that 'hey that dang Joey was snooping our board today' and perhaps do a little ball busting. Nothing more sinister than that.
Once again, not a big deal one way or another if it is/is not do-able, I guess I have way too much free time on my hands LOL