How to limit your bandwidth

[J.L. Coenders]

Hi all,
I have an ADSL connection to internet. When I am uploading somehting to the 
internet the upload blocks the download of other computers, which are also on 
my network. Is there some way to limit my bandwith of the computer uploading 
somewhat below the maximum of my speed. Perhaps per applications, or per 
user... It usually happens when I am doing a large upload with ftp and my 
mail checks or I am downloading something at the same time.
I searched the internet and found some things, but I wanted to ask you guys, 
but the hints there were pretty vague.

- Jeroen