Selenium - Selenium automates browsers. That's it! What you do with that power is entirely up to you. Primarily, it is for automating web applications for testing purposes, but is certainly not limited to just that.
Tricentis qTest - Tricentis qTest offers Agile testing tools to eliminate QA bottlenecks, ensure collaboration, and improve release quality. Start your free trial.
Oni - An IDE powered by Neovim
dotCover - JetBrains dotCover is a .NET unit test runner and code coverage tool that integrates with Visual Studio.
GraphWalker - GraphWalker is an open source Model-based testing tool for test automation. It's designed to make it easy to design your tests using graphs.
DevTest - Test management solution for efficient quality assurance