I had an idea somewhat like this a while back, but never worked out how to do it. Basically I wanted to "log anything" so basically you'd enter a quantity, a unit and what it was... and then later I'd figure out a way to make graphs and charts. This is clearly different, and the execution is good. I was a little confused by the interface early on, so some tooltips might be in order. I also wonder if a "date" type might make sense. I wanted to add a date to my list of items - maybe it would be a due date, or if you're listing things that took place, you'd like to add that to the list. Or just record when you had an idea that you want to add.
I liked the idea. There's also an enthusiasm coming out of it.<p>I got confused after trying it, because I kept thinking on the first screen that I was using it, while in fact I wasn't: I was supposed to be clicking on Next. I'm not sure what would be best, but I think I want to not go through the four screens that show me how to use it.<p>I wish the "Save" button was closer to "Add Item" so I don't have to move the mouse.
This is great.<p>I don't know why would one use it (why on earth would I want to share a list?), but it is a very well done thing.<p>Maybe this great interface could be used to power: public forms, enterprise data, a CMS like <a href="http://contentful.com/" rel="nofollow">http://contentful.com/</a>, a general purpose customizable CRUD app for small businesses.
Nice! Could see myself using something like this for exactly one of the use cases you described: looking for houses.<p>Found a bug: URL custom field type wasn't saving.<p>Also, grabbing images from a URL rather than download/upload would be a nice feature. Perhaps even grabbing an image from the URL field like a facebook or twitter share does.