I have used domestic award (or a free RT bump cert) to places that are usually somewhat expensive and/or last minute such as a funeral. For intl, I will usually use it for someplace that is expensive in coach in season (Australia comes to mind). Recently, I have spent the extra miles to go in Business or First. Best use of miles IMHO.

I have Business class booked on QF using my 95K US Airways miles. Since I got lots of bonuses last fall going to Europe on US, my cost of flying was very low.