Every Windows developer should give this list a once over when setting up a new PC:
Scott Hanselman’s 2014 Ultimate Developer and Power Users Tool List for Windows
There aren’t many I can add to that list - Scott has pretty much covered everything.
Here are a few things I would also suggest:
FFMPEG - if you do any work with video at all, FFMPEG converts things by command-line so you don’t have to install some dodgy app just to turn a mov file in an mp4 or whatever.