Camp 4 in Yosemite Valley has it's merits, even if it's only because you're so close to all that climbing. The Chasm Lake area in Rocky Mountain National Park is a beautiful area, and I've got excellent memories of the climbs I've done there. I'm planning a few more, too. It's not really a campsite, you're only allowed to use a bivy sack and you have to be there to do a climb. The campground at Wonder Lake in Denali National Park is excellent, spectacular views of Denali/Mt. McKinley. I spent a night there in 1987 before cycling back to the entrance of Denali National Park.
I spent a night wild camping around Ardnamurchan(sp?), near Castle Tioram, on my Scotland tour. Beautiful spot, but I don't think I could ever find it again.