The official release of Crown Polish, a simple command prompt interface for easily tracking Nuclear Throne crown unlocks. Note that you only need to download the executable, CrownPolish.exe.
To install, simply move CrownPolish.exe to the folder where your save file is. Usually that folder is C:\Users[YourUsername]\AppData\Local\nuclearthrone . From there you can create a shortcut and put that wherever is most convenient.
Here's a gif of it in action: https://gfycat.com/WhisperedSpitefulCopperhead