i don't remember where i saw it, but there was a tutorial where basically you make a batch file (using textpad and renaming the extension to .bat) including command line form render statements (like "render ineedrendered.ma -24 -29 camera01").

it basically just had 5 or so commands that change the frames of rendering and the camera that was being rendered from.

i think i did a google search for batch rendering. don't remember.