$$$This is probably not the answer you're looking for$$$ . . .but buying different needles is a good place to start. I've found that one of the best for non-slippage but still moving along are the Kollage squares. Which are about $15 each. They only come in dpns and circs, no straights at this point (actually they do have wooden straights which I don't like-- I'm talking about the aluminum ones). But for second best, Harmonies (called Symfonies in Europe) are great. I've also found that when knitting with bamboo, that the smaller the stitches, the less slippy it is. I don't know why, but if I'm using larger needles and larger sts, it's much harder to work with, but with smaller needles and smaller sts, it's far less of a problem:??.