PSQL is the command line administration/query tool for PostgreSQL. It is simple, light-weight and packed with a lot of charm. Unfortunately we can't quite capture all its charm in a single pager cheat sheet, but hopefully
this will give you a sense of its usefulness.
Below is a Thumbnail view of the PSQL cheat sheet. This is by no means comprehensive, but are the features we use most often. It is also pretty much what you get from the help screen with just some added color.