I happened on a strange little silicone-tipped "Double-End Detailing Brush" at Wal-Mart that I've not seen duplicated anywhere else. I'll try to get a picture up if I can find one online, or I'll have to wait until I'm back at the garage later this week to take a photo.
One end is a worthless plastic-bristle, straight-cut 1" brush with a sliding shield that I have glued in the 'full-cover' position as it annoyingly kept sliding back as I worked the 'booger' tip at the other end. THIS is where the magic is: It's a fingertip-sized nub of silicone that's chiseled to a point. Viewed end-on, it's shaped kind of like the bow of a boat, maybe about 0.75" in diameter at the base. It's very flexible and smooth - so it's gentle - and it's damn-near miraculous at working paste material out of body seams and fine details like the tight, inside edges of badging and emblems. It works like a tiny squeegee around the inner detail of my Mustang's "5.0" badges - so I don't even have to tape them. It's become invaluable in my toolbag!
They're not terribly well-made, but they are cheap. I bought one on a whim to try it out. A week later, I bought two more to keep in my bag. My first is just about worn after only 3 or 4 full details (I am pretty aggressive with it). If I ever run across a similar tool that's made better (or at least American-made), I'll jump on it. But for now, I won't compound or wax without my "booger-stick!"