My latest quickie DIY project: a birthday card with a tiny bunting of miniature flags. If you want to try one, here's how to make it.
Fold a sheet of cardstock into thirds, accordian style. If you want a printed message on your card, run it through your printer before folding.
Cut out strips of colored paper and fold them in half lengthwise. (My strips were about 1" wide.) Cut the folded strips into tiny triangles; they should look like little hinges. Make a few strings of bunting by folding triangles over a cord and gluing both halves together.
With an X-acto knife, cut tiny slits in the folded edge of the cover of your card. Thread one end of each bunting cord through a slit and secure the cord end behind the cover with a piece of tape. Wrap the opposite end of each cord around the cover of the card and secure it in the back with more tape. Then place double stick tape around the edges and center of the back side of the cover and stick the cover to the adjacent panel, hiding the taped ends of your bunting. Round the corners of your card if you like, and you're done.