AstroPlot is a small, fast and free tool for visualizing 2D data, slightly inclined towards usage in astronomy.
With AstroPlot you can: plot any number of data-files and functions, move around your data by zooming and panning, decorate your plots using various colors, fonts and different drawing styles, export your plot as a picture or print it, and much more!
Current version is 1.0.1, released on April 9 2008