Show all files in Finder
As a computer professional (just kidding), I prefer to see all files in the file system and not just the ones that Finder or Explorer wants us to see.
In Windows, you can easily just check a checkbox to show all hidden files in Explorer. In OS X, however, you have to type the following in a terminal window:
defaults write com.apple.finder AppleShowAllFiles TRUE
This will show all files in Finder, hidden or not. To disable this feature, simply enter the following in a terminal window:
defaults write com.apple.finder AppleShowAllFiles FALSE