I just married Maxima and Euler. Euler is a MatLab like numerical system
with a GUI frontend in notebook style ala Maple, plot features, and a
numerical programming language. There are versions for Windows and Linux.
Currently, Maxima can only be used in the Windows version of Euler.
Euler can be used as a GUI frontend to Maxima. It can also exchange data and
expressions with Maxima, helping Maxima with numerical calculations, and
Euler with symbolic evaluation.
More information and download from
http://mathsrv.ku-eichstaett.de/MGF/homes/grothmann/euler/
Euler is open source.
The Maxima interface is currently in Beta. I am asking all Maxima experts to
point any errors to me. Thank you!