How many times have you run a dd command and sat wondering how much longer it's going to take to complete? Maybe you're sat there with another Terminal windows open running 'ls -al' incessantly to monitor the size of the output file? This was me until I discovered the 'pv' command; rather later in life than I'd have liked.
Pipe Viewer (pv) is a Linux tool that simply monitors data being passed through a pipe and provides a progress bar.
I have since found many, many uses for this tool and wanted to share a few of my highlights so far: