I just finished making zezti.com. I wanted something to help me keep track of what groceries i had and what i needed, without having to maintain a list. Zezti does just that, so i can check a list of exactly what i have in my pantry from the store. It also has a list for the old-fashioned folks.
While making this, i also learned Rails, JQuery, and JQuery Mobile. It is still a little rough, and I have heard that is certain situations, when adding an item to a list it starts looping. I have not yet been able to isolate it, but if you do, that would be hugely helpful. I hope you enjoy using this. (Sorry, the initial page load is rather slow, I'm working on it.)
P.S: There's also a mobile version at m.zezti.com