Bar is a simple tool to copy a stream of data and print a display for the user
on stderr showing (a) the ammount of data passed, (b) the throughput of the
data transfer, and (c) the transfer time, or, if the total size of the data
stream is known, the estimated time remaining, what percentage of the data
transfer has been completed, and a progress bar.

WWW: http://clpbar.sourceforge.net/