I cut "rings" out of an old knee high w/ a run in it and loosely wrap them around spools of monofilament. I have no troubles keeping the tension, and the thread doesn't come off the spool before the machine pulls it, eliminating snarls and tangles on the spool pin.
And, not really quilting, but when making ruffles (curtains, pillows, bags, etc.), I use dental tape instead of a ruffler foot. It never breaks when gathering (and has the bonus of being able to undo when you need to wash a curtain).