Scratch files are mentioned in the release announcement for IntelliJ 14 but it does not mention how to create or use them. Any links to documentation would be extremely helpful.
What I Have Already Tried
I have already performed several web searches for creating scratch files and the only things that have turned up are articles talking about the feature, none of which specify how to actually use the feature.
I have also tried "File"->"New...", but there is no option for scratch files.
I did find some documentation on scratch files in a PhpStorm plugin, but, despite both being JetbBrains products, that appears to be completely unrelated and none of those shortcuts work.
Tip: you can find any action in the menu "Help" -> "Find Action...".
This specific action is in the menu "Tools" -> "New Scratch File...".