Foi dica de um leitor anônimo, no POST Software livre para trabalhar com ERP / CRM !, eu não conhecia, gostei muito das FEATURES deste CRM, sem falar na interface gráfica que é muito caprichada.

vtiger é um software CRM Open Source, para pequenas e médias empresas. Ele foi criado em PHP, 100% compatível com LAMP/WAMP (Linux/Windows, Apache, MySQL, and PHP) e outros projetos opensource.

Features

Sales Force Automation	Customer Support & Service	Marketing Automation
Lead Management	Trouble Tickets	Campaign Management
Account & Contact Management	Knowledge Base	Mass Mailing
Opportunity Management	Customer Self Service	E-mail Templates
Sales Quotes	Online Knowledge Base	Mail Merge Templates
Inventory Management	Activity Management	Productivity Add-ons
Products Catalog	To Dos, Meetings & Calls	Email Client
Price Books	Recurring Events	Outlook Plug-in
Vendor Management	Shared Calendar	Office Plug-in
Purchase Orders	Activity History	Thunderbird Extension
Sales Orders	E-mail Notifications	Customer Portal
Invoices	Notes	RSS Feeds
Reports & Dashboards	Product Customization	Security Management
Key Metrics	Custom Fields (10 different data objects)	User Management
Customizable Reports	Pick Lists	Profiles
20 Pre-built Reports	Custom List Views	Roles
20 Pre-built Dashboards	Drag & Drop Modules	Groups
Report Folders	Currency customization	Organization-level Access Control

Referencia: http://www.vtiger.com