SugarCRM is an open source (and commercial support optioned) CRM platform - they have multiple licenses, variations and releases as well as a hosted platform option. If you're not familiar with CRM, it's basically a portal-style webapp that helps your sales force (sic) maintain sales leads, contacts, business relationships, and so forth.

At it's core are the basic organization tools - you have business (accounts) with contacts whom you maintain relationships; a CRM lets you store notes, call times, business discussions, and things like that (you can use as little or as much as you need, many CRM systems offer a lot more features).

SugarForge: Open Source CRM, SugarCRM, Sugar CRM