pfSense - pfSense is a free and open source firewall and router that also features unified threat management, load balancing, multi WAN, and more
6sense - 6sense is a B2B predictive intelligence engine for marketing and sales.
Zentyal - Linux directory, domain, mail, gateway and infrastructure server for SMBs.
Leadiro - Seriously Smart & Live B2B Data
NethServer - NethServer is an operating system for Linux enthusiasts, designed for small offices and medium...
ZoomInfo - ZoomInfo is a B2B database providing detailed business information on people and companies.