xsltproc is the most widely spread XSLT 1.0 processor with many EXSLT extensions.
The program xsltproc comes with libxslt, which is part of the gnome project and is therefore available on most Linux installations and also on Mac OS X. Find it out by typing on the command line:
If its not there, check your package manager and install libsxlt.
Also on other platforms it is very common. We know of binaries for