I got a thing through the post from Homebase - "your current balance is 12022, that's worth £60.11" 
It would be worth £360 in Clubcard deals!!!!
I've traded some in for wine when they were worth double, but that seems to be as good as it gets. I think once I've used the ones I've got I won't bother saving them again (that'll fox Sainsburys
)