Download Electrostatic Potential Solver
The elstat PDE solver with GUI runs natively under Linux and uses the Qt toolkit. Porting it to other Unix/X11 platforms should be easy, porting to non-X11 platforms will require more effort (because the fast graphics display is done using raw XLib instead of slow Qt).
As always, I recommend downloading the source code and compiling it yourself. In case you want to do that, you need a C++ compiler, preferrably the Gnu Compiler Collection (GCC), at least version 3 (version 2.95 may work, too) and the Qt toolkit which from TrollTech is available for free if used non-commercially under Linux (most Linux distros already come with it - install the devel package).
Download this file for ElStat source code:
After downloading the source, unpack it and go on with the INSTALL file in the toplevel dir.
Of course, it is more convenient to download a binary package.
However, since this involves a lot of C++ code, you need a lot of
shared libraries using the same (major) version as I do compiled with the
same (major) compiler version. This is very unlikely.