Xpdf runs under the X Window System on UNIX, VMS, and OS/2. The non-X components (pdftops, pdftotext, etc.) also run on Win32 systems and should run on pretty much any system with a decent C++ compiler.
Xpdf is designed to be small and efficient. It can use Type 1, TrueType, or standard X fonts.
Xpdf should work on pretty much any system which runs X11 and has Unix-like (POSIX) libraries. You'll need ANSI C++ and C compilers to compile it. If you compile it for a system not listed on the xpdf web page, please let me know. If you can't get it to compile on your system, I'll try to help.