Finmark - Financial planning software for startups
Zabbix - Track, record, alert and visualize performance and availability of IT resources
Poindexter - The easiest way to create financial projections for new business ideas. Quickly determine the profitability of your strategy without using Excel.
Datadog - See metrics from all of your apps, tools & services in one place with Datadog's cloud monitoring as a service solution. Try it for free.
Pry Financials - Finance for Founders
Wireshark - Wireshark is a network protocol analyzer for Unix and Windows. It lets you capture and interactively browse the traffic running on a computer network.