Topic: Recipes
As of the time of posting this, there are several apps that will show a single recipe:
Recipe Fetch by gonga - my personal favorite due to flexibility
In general all of these apps can show 1 recipe, offer no flexibility, and no ability to post and reference your own recipes. There are lots of possible systems for describing a recipe, lots of way to store them, make them searchable, etc... but most of all I wanted to start a discussion on what we, as a community are really hungry for (bad pun, I know)
It may also be of interest that the way US copyright law is written, recipes are not entirely copyrightable. their arrangement (as in a cookbooks order) or their artistic description (the exact wording of instructions, any diagrams) are protected, but not the ratios, or the actual procedure. This opens the door to copying and citing recipes, or even easier to defend legally would be to cite your "inspiration" and then paraphrase the instructions.
I will add my own recommendations for format below in a separate post once I have thought about it for a few days. Let the ideas fly!