Ever wanted to diff the output of two commands? Usually it’s done by first piping each command to a temporary file and then diffing them.
The following syntax creates a named pipe for the command and uses the pipe’s name instead of a filename. Bash takes care of everything automagically so all you have to do is:
sort <(cat /etc/passwd)
That’s a dumb example, but how about this?
diff <(command1) <(command2)
The commands can be as complicated as you need them to be!