Limit URL Bandwidth?

[snagrat]

We are constantly maxing out a 100meg leased line due to our demands on sharepoint.com. A new 300meg line is on its way but for now I need a way I can limit the download from sharepoint.com to atleast 75meg.

 

We are SWGfL at the moment with a Lightspeed rocket. Lightspeed say they cannot do it so I was wondering if there is a simple free tool we can install that would sit between network and internet so we could control the bandwidth of such sites?