Network Monitoring?

[Pancake]

So here is the situation, we have about 4mb ADSL, and if someone is downloading at full speed its pretty much useless for anyone else.

So we all agree not to download before like 1am so everyone can use the net.

It seems every other day someone decides to download something and everyone is complaining its slow. I have 1 part of my plan sorted, the Android App WIFIKill that got pulled from the market almost instantly, its an app for rooted phones that uses ARP spoofing and redirects everything on the selected ip to 127.0.0.

Now all i need is some software i can see whats on my LAN and how much BW its using, is there a such thing? my router info is useless for this

[smargh]

m0n0wall + alix box. Perhaps more expensive & has a slight learning curve, but it's a longer term zero-maintenance solution.

[Pancake]

I could just use an old laptop with 2 LAN cards? i have a thinkpad T41 with a smashed screen i could use

Wont be expensive at all then, and i like to think im a pretty fast learner so it shouldent be a problem