A short and sweet one today: dnSpyEx advertises itself as a debugger and .NET assembly editor, but for me, it has been used just as a very nice decompiler when I need one.
Most of the time these days I tap CTRL+F12 in Visual Studio or Rider to peek into the source code of external dependencies and then I don't need a decompiler. But I still find myself looking at random dlls that are not part of any solutions that I'm working on at that moment, curious as to what's going on behind the scenes. For those situations, dnSpyEx is most excellent.
I am drawn to the features for debugging and modifying dlls, but I haven't found a use for them yet. It sounds very powerful though!