Program to monitor connection?

[Levone]

Is there a program that monitors what is downloading/uploading from your computer/connection? Currently I have a gadget (windows 7) which says I'm downloading 250 kb/s, but I'm not downloading anything at the moment, which means either the gadget is wrong (which is entirely possible) or something unknown to me is downloading (which has me worried). So is there a program that would tell me more specifically what's happening on my line beyond just numbers?

 

[Homenet]

Wireshark will monitor every single packet in/out of your network connection. It requires a bit of learning to understand exactly whats happening but once you do you'll be able to track down where all that data is coming from / to.