I'm a big fan of sending (and receiving) cards via snail mail. I think email is nice and evites are free, but isn't it great to get something in the mail that doesn't ask for a "payment due by" or "vote for ________". For Mother's Day I made the mom's in my life some scrappy cards. I just picked up a pack of blank cards from Michaels ($4.99 with coupon), and used scraps from my growing bin of scraps.
It's one of those projects that I don't think you can really mess up. It's fun mixing and matching the fabric and seeing these mini quilts, if you will, come together into a fun gift set.