I'm 2/3 through a sweater, so in the meantime here's something we did last week. I got the great idea from Leslie and I thought my 4 year old would be up to it on an otherwise (unusually) empty afternoon. Blow up a balloon, put it in a bowl, cut lengths of various yarns, run them through some white glue that will dry clear or clear glue (I used slightly diluted glue - don't do that), stick it to the exposed part of the balloon, let dry about 3 days, pop the balloon and voila. Something to hold your hair ribbons. Or lego.
It's a bit fragile. This one's been to 'Show and Share' and back and looks worse for it. Maybe closer spacing on the yarn application would help. More attempts are in our future.