From the party line:
For each new fan you bring here on Facebook we will give you a 20% discount on your next order!!! RULES: You just have to tell the name of the friend(s) you brought to our page and we will ask them a confirmation. You get a 20% discount for each new fan you bring to us, but those discount aren't cumulative, so if you bring 3 friends you receive 3 different 20% vouchers for 3 different orders. The offer i valid until 10th of March.