quickplot

Quickplot is a fast interactive 2D plotter with infinite zooming, value picking, pipe input, and almost unlimited plots displayed.

Quickplot is meant for looking at your data quickly and of secondary importance is making static pictures of your data. It's a data viewer, not a plot editor. It reads ASCII text and sound files. It has lots of command line options, making it very shell script friendly. It currently runs on GNU/Linux systems and I hear it works on Mac OS X Darwin.