Grace

Grace is a point-and-click tool that allows the user to draw X-Y plots. This is the program formerly known as Xmgr.

A few of its features are: User defined scaling, tick marks, labels, symbols, line styles, colors, polynomial regression, splines, running averages, DFT/FFT, cross/auto-correlation, batch mode for unattended plotting, and hardcopy support for PostScript, FrameMaker and several image formats.