Tim - I feel you on that one! I try to squeeze every mile I can safely get out of motorcycle tires. I don't really know why I run them down that low, it's not like they're super expensive. Hell, I can order a complete set of front and rear tires for the Hawk and still not hit the 'Free Shipping on Orders Over $99' threshold.
I'm going to have to buy a new rear tire for the DR, as well as a new rear tire for the Ural pretty soon, so I'll probably just get everything all at once.