DIY Crochet Miniature Postage Stamp Tutorial and Pattern from LIttle Woolie. This would make such a good gift with other stationary items.
DIY Ribbon Banner Tutorial from Damask Love here. For scrapbooking, cards or photo albums.
DIY Top Ten Free Printables from The Wedding Chicks here. These printables are really fun because you get to choose from so many colors for each element. At Michaels you can buy (on sale) thick cardstock cards and envelopes really cheaply that you could run through the printer to make really nice stationary. *First seen at Crafting Rebellion here.
A few that I did for fun (clokwise from upper left):