Hosting video outside of Pro Tools as a slave

[NGati016]

Hi everyone, I am new to the Avid forums. Can anyone help me with this question? If I want to host video outside of Pro Tools because when I score music all of the plug-ins, VI's and the video seem to have a lot of weight on my computer. Since Pro Tools is not 64-bit yet and can only access up to 4 GB of RAM (...or so I've read), I can't use all of my computer's RAM which is 8GB and soon I'm going to buy more to get up to 16GB. Is there a way to host video on my computer as a slave to ProTools so I can edit and record, etc. within Pro Tools but watch/control the video from another source, but still within my computer? Basically, is there a standalone program that can do this? If so, how much is it and what do you guys use when composing music for film and have a lot of plug-ins and virtual instruments going on...PLUS a large video?
Thanks!