Zoho Invoice - 100% free online invoicing software for small businesses.
Office Timesheets - Professional Services Automation
GTreasury - GTreasury provides solutions to automate and streamline all repetitive treasury processes.
HarmonyPSA - HarmonyPSA - Professional Services Automation (PSA) for IT Businesses
Icinga - Icinga is a fork of Nagios and is backward compatible.
Timewatch - Timewatch offers time tracking, expense management, resource scheduling and professional services automation solutions.