I was given a code to share for first time buyers:
Your refer a friend code is: QFHAJW
Your code gives free standard shipping to anyone making their first purchase with MOO, and is valid until August 31st, 2009. Your friends' individual purchases must be over $15 to qualify.
Anywho.....let me know if you want more info. I highly recommend these Moos. I will definitely be ordering some full-size business cards from them too. :)