Lpc2000

Hand-made makefile and command-line.
Because of the ability for fine-tuning a compilation process.
We've used Visual X-Tools IDE, but there's no some features for
command-line compilator's options, thus the only variant - writing a
makefile by ourselfs.

Maybe there's some IDE under GPL, but we didn't interested in it,
thus, didn't find it.

As for syntax highliting during editing source files, there're a lot
of tools for linux (working either in text-mode, or in graphical mode
under X-Windows).