Montai is a project mainly written in C and PERL, it's free.
multi-threaded inkscape renderer
Montai is a multi-threaded renderer for Inkscape.
Inkscape is an amazingly powerful SVG production studio with one glaring flaw - it's renderer is single-threaded.
Montai breaks up SVG files into pieces comprised of work units and uses as many threads as you like to render each piece.
Enjoy.