Sweet!
Not a bad idea....kind of smart...
I think it would be sort of helpful for the younger generation to keep an eye on your kids and stuff...however...I can think of so many ways to work around that that I am sure kids have not thought of already...
--putting ice pack on the area to lower temp
--switching underware w/ a friend (its grouse but it would help you save your ass from getting caught doing something naughty--literally)
--switch the underware like on your dog (they have heat too...lol...I know cause my Rott set off our motion detector cause he's so big he's a huge heat source)
Now all they need to do is make something to where its hidden instead of a little star, or heart or something cute on the side of your undies.
And what about males? Common girls you know if your ass could put one on a man that you think you needed to keep your eye on you would do it!