rob, your assumption is right .... background services
http://vsl.co.at/upload/users/449/backgroundservices.gif">
as a rule of thumb for standard machines with not too much RAM (512 is still pretty common) it is recommended to have the same amount of virtual as physical RAM, sometimes even more.
for audio machines (where you should really have 2 GB RAM or even more) it doesn't make sense to have virtual memory - you woudn't want any application to use it (even if it could) for performance reasons.
to let windows decide if and when to move assumed unused data to the pagefile can result in unexpected hickups
christian