I\'m really liking the IntelliJ diff tool. I\'m wondering if it is possible to use this tool to diff two arbitrary files. I.e. files NOT in an IntelliJ project. Just pick tw
Yes you can (of course, if we are talking about text files). But probably you will need to create some project (just for opening there files).
Then your steps will be:
1) Add to created project file#1 and file#2.
2) Open file#1 in editor
3) Right click mouse in left menu (project files browser) on file#2 and find menu-item Compare File with Editor.

That's all. After p.3) a comparison windows will be opened.