> Out of the 100, maybe 25 are "thin as a human hair" and therefore > pretty useless.
I'll take any of the 13's (#80) and 14's (#79) you'd otherwise discard. I use those the most. Or you could do what I do, and use those for through vias - they're perfect for wire wrap wire or the individual strands from 22 gauge speaker wire. Assuming you can drill without breaking them, of course.