A place to centralize the great work @mathiasbynens did gathering and foster a community around finding and documenting OS X default configuration from the command-line.
Want to see all, and I mean ALL of the default values on your system? Open up your command line and type the following:
defaults read > ~/defaults.txt
Just want the values for a specific application? No problem. Here's an example:
defaults read -app iTerm
Source: Mac Developer Library