OK I'm going to try and tackle as many of these questions as possible.
At Mac the DC++ works as follows: One student (usually an upper year tech-savvy student) will get it up and running and you will soon hear word that it's ready to use. You download and install the program, and basically pick and choose files on your computer that you want to share (allow others to download from you). You're going to want to share your music, movies, games, and whatever other media files you may want. If everyone does this, there will be a large collection of STUFF to download. If you're bored one night in rez, search for a movie and you'll most likely be able to download it. Also, since it's exclusive to the Mac LAN, speeds are blazing. You'll be able to download entire music albums in
literally 2 seconds. Usually you'll get anything between 5 - 20
megabytes per second. I believe there is a version of DC++ that works for a Macintosh computer, called
Shakespeer. I never checked it out because I have Windows, but check it out once you move into rez.
A word about torrents: The McMaster firewall is quite comprehensive, and blocks almost all ports that can be used for torrents. I tried it a few times myself and got pathetic speeds (in the neighbourhood of < 1kb/s). I heard rumours that some people were getting normal torrent speeds but never saw any proof of it. So your best bet is probably to stick to DC++.
On the other hand, if I ever missed an episode of LOST it was usually up on DC++ a couple hours after it was on TV, so someone on campus must have been downloading it. How they went about doing this, I'm not sure. If you're very tech-savvy, you'll be fine.
If you exceed the bandwidth limit, McMaster will choke your bandwidth for the next 24 hours. This can be very annoying because you'll have trouble doing simple things like loading web pages and using MSN. So I suggest doing everything in moderation so you don't cause yourself the inconvenience.
With regards to gaming, you should be able to connect to public servers on most of your PC games. My roommate, who had a powerful gaming PC with tons of online games, was able to play Battlefield, CounterStrike Source, and everything else on the regular public servers. Also, many of the people on DC++ like to organize regular games of CounterStrike 1.6 through LAN. It's pretty fun, but be prepared to get your ass handed to you most of the time
.
That's about all I know for now, good luck!