i have some park tool that's got a one-tooth "lockring spanner" on one end, and some wacky 3-tooth spanner on the other end. the one-tooth end sucks, but the 3-tooth end works real well. doesn't slip off. let me see if i can find a picture.

yup. this guy:
http://www.parktool.com/products/det...5&item=HCW%2D5

works like a charm on lockrings. yes, trackhub lockrings. not just bb lockrings.