SciDAVis

SciDAVis is a free application for Scientific Data Analysis and Visualization. It combines a shallow learning curve and an intuitive, easy-to-use graphical user interface with powerful features such as scriptability and extensibility. SciDAVis runs on GNU/Linux, Windows and MacOS X; possibly also on other platforms like *BSD, although this is untested.
Find SciDAVis at: http://scidavis.sourceforge.net/