Re: Assigning bandwith to a pool of PC's and leave the rest for public use (wireless)
I have been looking for such a thing myself for a while now. But all I could come up with is a bunch of simplistic GUIs and some more powerful command-line tools. If you search sourceforge.net for the terms "traffic shaper", you will be presented a whole list of tools, but I couldn't find any which I would recommend. You might want to have a look at them.
Alternatively, there is the Linux built-in tc (for "traffic control"), which you can do almost anything with. It is a little hard to configure, though. I can only recommend reading the "Linux Advanced Routing and Traffic Control HowTo" (to be found here: http://lartc.org/howto/), if you want to go that way.
If anyone else comes up with a good (GUI) traffic shaper, I would appreciate it very much.
BTW: You talk about sharing your Internet access with "other people". Do you know (or even better: trust) these other people? I highly discourage giving strangers access to your private Internet access, because they might do evil stuff (like hacking other computers on the Internet) and your address is the first to come by, when the police finds out that computers were attacked from your IP address.
Mark threads as SOLVED, when they are. More importantly: let people know what actually solved your problem and do not just let the thread die.