ListPhile – Shared Lists, Atlases and Databases
http://www.ListPhile.com/

Listphile is a powerful tool for organizing and collaborating around structured information. Call it a database tool, if you will. Listphile was borne of curiosity, and the belief that we learn more effectively when we have a framework for collaboration and knowledge sharing. Listphile is:

Free
Open
Flexible
Powerful
Mashable
Shareable
Grassroots
Easy to use
Embeddable
Collaborative
Customizable
Borne of curiosity
Built with Ruby on Rails
A cool new way to make lists
Obsessed with self improvement
New to the world, as of September 2007
Created with open source software
Focused on adding features that *you* want
A great way to create a list, an atlas, or a database

This has been added to the tools section of Research Resources Subject Tracer™ Information Blog.