Our app was designed to solve a problem we run in to frequently - giving clients ball park estimates over the phone or via email. Not the kind of estimates you spend 15-20 minutes on in professional apps like QuoteRoller or Quotient - the kind of ballpark estimates that many freelancers / small scale projects require as a "before you even start talking, about how much would XYZ cost?"
This app was designed for us to be able to quickly create a decent looking ballpark figure, and retain the ability to quickly reuse items, or allow people like our designers to help estimate things like a simple wordpress site, hosting, etc if a developer or PM isn't around.
Due to some of knockout.js functionality, this doesn't work on IE7 as best we can tell. Obvious favorite is Chrome, but it should be ok in any modern browser.
You can use the login/register form to create an account and login by expanding it, and filling it out. Once done, you'll be at your dashboard. Here you can use the main center form to create new line items, categories, and price ranges and add them to the current "ballpark." If you want to save them for late, click the blue "add and save" - when you're done click "Save Ballpark."
After that's done, you can click the ballparks tab in the left sidebar, and then click any of the titles to get an html version of your estimate and a URL to share.
If by chance I can pull it off, you'll be able to use the "Items" tab on the left to click and auto fill out the ballpark line item form.
We use a small range of node modules for this app - Express 3.0, Jade, BCrypt, Nano, and UUID.
For our database we opted for Couch - we have been using a neo4j graph for social apps but didn't feel that would work here. Would have used mongo but with not having used it in awhile we felt like a quick-and-dirty CouchDB document store was the best bet.
Client side libraries include jQuery, Twitter Bootstrap, and Knockout MVVM.