I recently took advantage of a great sale going on at VistaPrint and purchased 100 business cards. They're still having a the sale, but it ends soon. Right now you can get 100 "Mommy" cards for just $1.99 plus shipping. These are great- pretty cards that you can personalize with all the information that you want. There are lots of options- I got cards for my blog, but you can also get cards personalized with your kids' information, perfect for handing out at school or at the playground. There are a number of options for how exactly you want to personalize your cards.
I'm really happy with how my cards turned out- now I just need an event where I can start handing them out!
Here's a picture of my card (minus my phone number, that is on the actual cards, but I didn't want to publish it here):
Disclosure: I received no product and no compensation for this post- just passing on some information!