I often have to mail a single ATC or a small handful of inchies, and I like to nestle my art in a small, flat card, nothing too special. Today I made a bunch of them, using the Petit Four technique from the Technique Junkies newsletter. Basically, you cut four cards out of a 12x12 piece of cardstock, and score it in such a way that it makes a sort of gate fold.
I was looking through my designer paper, looking at the Easter prints, when I came across a sheet that had 4 potted plants across the bottom, and a soft print over the rest of the sheet. Papers like this are great for scrapbooking, but usually not so good for cards. It was double sided cardstock, so it wouldn't need much decoration, but how was I going to get the images on the outside right side up? I wasn't, and then it hit me that they would look great on the inside.
Here's my card, closed (3x6 inches). The only embellishment is an embossed butterfly, glued to the top fold.

This is how it looks with the bottom fold flipped open, so you can see the plant.

Cool, huh? I knocked out four of these in just a couple of minutes - perfect for holding my little artsy cards.