Brad Sams, Neowin:

Here is a bit of news that will leave you scratching your head for anyone that uses OS X Mountain Lion. If you type "File:///" (without the quotes) into nearly any app, it will cause the app to crash. This odd bug has been confirmed by Neowin and we have managed to crash Spotify, Tweetbot, Notes and a bunch of other applications too.

Apple's software gets sloppier all the time. Note that the "F" has to be capitalized. I tried this in Safari, Chrome, and Tweetbot, and it works like a charm. Even if you just type it in a search box; even if you don't hit Return. I hope this gets fixed fast.