What would I do with them??? Well, they are pretty cute on their own, but I thought that they could be the starting base for something else - maybe something featuring one of the Sale-A-Bration stamp sets from Stampin' Up. You see below that the So Many Scallops set when stamped and punched out fits over the printed motif. So basically, you are using the background already provided on the notecard and adding your own touches.
Keep in mind that this doesn't just have to be for these itty bitty cards. I've picked up printed notecards in mailable sizes that can also be embellished/altered. It's a great starting off point, especially if you don't have a lot of card stock. I can't say that that was the reason they caught my eye though. In all honesty, I loved the little colored envelopes and was going to make up my own cards to fit them, but decided on this route.
Now you might ask, what would I do with something that size? They make perfect gift enclosures, lunch box tuck ins, or you could even put them on a regular size card or in a scrapbook!