If you're into cooking then MacGourmet is a great app for helping you create and edit recipes as well as make notes on your favorite foods.
It includes features for taking wine and cooking notes as well as allowing you to easily browse your entire collection and make a truly customized cookbook. The developers like to call it "iTunes for Recipes" and you can see why in the way that MacGourmet brings an iTunes style look and feel to recipe writing and cataloging on the Mac.
One of the other great aspects of MacGourmet is that you can share your recipes and favorite dishes with others by uploading them to MobileMe and WebDAV accounts. You can even publish directly to TypePad and MoveableType blogs (although not WordPress unfortunately). It can also export ingredients to your PDA and iPhone to make instant shopping lists.
Searching MacGourmet is a breeze although some users will notice that a huge number of the initial 80 recipes that MacGourmet comes with to get you started, are meat dishes so vegetarians beware.
There really is little to fault in MacGourmet beyond that. You may have trouble searching for obscure or non-American names ingredients but overall, it's a cook's dream.