DanceSafe has been doing their form of this for years in the US.
Check out the Book Thing of Baltimore if you're around Charm City some weekend. Russell just gives away books. You show up to the "free book place" and take as many as you want. The minimum is ten (he really won't let you leave) and the maximum is 150,000 books per person per day. Corner of 27th & N Charles St, look for the Free Books signs. Open Saturday & Sunday 9 AM - 6 PM.
This isn't an ad, but honestly a post from someone who knows & loves books -- especially those at the Book Thing. I was turned on by a friend, and I've introduced my friends and so on. Probably 95% of the books I've gotten in the past two years were from the Book Thing.
No really, they're free
"The eleventh commandment was `Thou Shalt Compute' or `Thou Shalt Not Compute' -- I forget which." -- Epigrams in Programming, ACM SIGPLAN Sept. 1982