A granny star 'lap blanket' for my dad to cover his legs with while he is reading. The yarn was a 3 pack from Amazon, each ball was 150g/530m. I do a centre pull and used the balls in order of which centre closely matched the outer of another ball and it seems they came from the same lot so they matched up really well and changed colour near perfectly all the way around. It also wasn't a full ball of white, just 2 rounds to finish off and make it look more uniform. I don't actually know how long it took me, I did it bit by bit over several weeks but if you're quick and have time you could probably do it in one or two days.