Seehere: 25 Free Photocards
Seehere is offering this week 25 free photo cards. You still need to cover shipping which is $4.99. I think these would make for some great birthday party invites or announcements.
Edited to add: According to Natasha at Saving a Bundle if you only order 24 of these you get free shipping for $2.49. You may want to check that out if you are ordering these.