For over a decade Total Commander has been the Windows File Manager replacement of choice for system admins and old school power users alike. A major new release (v9.0) offers a wide range of user interface improvements, functional enhancements, and a wave of bug fixes. There's an Android version, too. Download it here.
Vivaldi rose to fame as the Chromium-based browser developed by the creators of Opera. Since then it's continued to be fine-tuned into a great browser alternative to Chrome and Firefox. Feature highlights include tab stacking, side by side tabbing, built-in note/screenshot taking and most recently control for Philips Hue color lights.
Odds are you know what's in your PC, like the processor model, how much RAM you've got, and what GPU. But how about when you are trying to troubleshoot your work PC or a relative's. Piriform's Speccy (from the same guys that make CCleaner) is a straightforward solution to find complete specs about your hardware and software in a single place.