A different yarn holder idea

My gd went to Marine World this weekend and brought home a big soda cup that has two holes in the top of it. One hole the straw goes into and the other hole is to put the top of the straw into so you don't spill your drink. Any way I was just looking at the cup and lid cuz the kids have taken out the straw and are playing with it. This cup would be nice for a yarn holder. Already has the holes, you could use 2 balls of yarn even.