Internet traffic monitor

A friend of mine uses iStat Pro to monitor his internet traffic on the Mac. I really like this application but I am on a PC. Is there anything on the PC that will monitor the amount of traffic going in and out of my PC. I am concerned that there is something running that is killing our internet speeds.

take a look at "Active Ports" http://www.tucows.com/preview/213738
That monitors all open network ports and tells you which programs have network connections, and to where

Hi Jon,
I have downloaded and installed Active Ports. It was good to see all of the connections but it does not show how much traffic each connection is using. Can you recommend anything else? Also, why do Mac users get such a pretty interface and all we get is rows of text.

James

turns out Microsoft have a recently released version of their own network monitor. I've never used it, but it looks worth a look
see
http://blogs.technet.com/netmon/archive/2008/09/17/network-monitor-3-2-has-arrived.aspx
andhttp://www.microsoft.com/downloads/details.aspx?familyid=f4db40af-1e08-4a21-a26b-ec2f4dc4190d&displaylang=en