If we're talking about the bands you tie your hair up with, I've always called them hair ties.
Anyways, is your driftwood smooth, or does it have holes where you could possibly wedge the rhizome of the Anubias down into? That's what I've done with most of mine. They should eventually grow more roots, and take hold of the wood, and that's how they grow in the wild.
Ooh I see it was a rock you were talking about. I wedge all mine between a couple of rocks and let the roots hang in the substrate. Or I did buy some elastic string used to make jewelery at the craft store to hold my java ferns in place and that lasted ages in the water without breaking and didn't seem to harm my goldfish.