A company called Moo made a big splash a couple of weeks when they announced a new product -- MiniCards -- that could be printed from your Flickr photostream. To get buzz going, they gave away 10,000 packs of 10 minicards to Flickr Pro users (the cards are normally $20 for 100).
Of course, you have to follow up buzz with product. I got my free pack this weekend and I have to say... eh. I have three problems with the Minicards. First off, I wasn't ready for how mini they are -- about half the size of a business card. I'd be worried about losing them before I could give them out. Second, them seem really dark to me. Shots that I know have pretty vibrant colors, like our jumping wedding shot, came out rather murky, I thought. And lastly, the mini-cards are, of course, gang-printed (that is, printed a bunch to a page and then cut out) and I was surprised at how many of the cards had a strip of someone else's photo down the side. You'd think that for your "show off to the power users" batch, you'd take extra care with stuff like that.