Coffee Grounds

I have "secured" (asked te coffe kiosk at work!) a decent supply of coffee grounds. Probably a bucket full every two ro three days, what is the best use for them.  I am pretty sure that I can compost them but what else??

I've also read that they can be on the acidic side. I got some a while back and plan to use it as a mulsh (along with some pine needles and peat) around my blueberries - when I eventually get them planted out on the allotment that is.