Get a VPN client like http://www.witopia.net/welcome.php, it will encrypt and proxy your traffic so your school admins won't be able to determine the actual destination of your traffic or what traffic you're sending.
Also throttle your connection because, as someone who does this stuff for a living, I'd be able to track down who's utilizing the most bandwidth on a WAN link in about 5 minutes and if you're consistently using the same subnet you're probably leasing the same IP over and over, which makes you easy to track down. Even if you're encrypting your data, I'll still be able to track the source IP and if I saw nothing but SSL traffic I'd have someone physically locate you. That being said, if you're throttling your traffic, you won't throw up any red flags. If you're using Utorrent you don't have to download any extra applications, just change your bandwidth settings by going options -> preferences -> bandwidth; if you're not using utorrent, use utorrent: http://www.utorrent.com/
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Noticed you're already using utorrent, good stuff.
I personally love witopia. I've been using them for a year and no complaints. Great prices, and you can even split it with a friend.
But yeah, you mean VPN client. A server would mean you want to rent a computer which goes for about min $50/month
ah I feel retarded, I forgot there was another thing I purchased that goes along with Viscosity, the actual VPN, I used Witopia it's another 40 bones, but that's where I get all of my cities from within Viscosity, but if that's the route you are going to go, I promise you it 100% works. I feel like a turd that I completely forgot about that, I'll figure out a work around for you guys if you don't feel like buying it.
I also recommend Witopia. It's a really great VPN service that I used for the past five months in china. There are multiple types of services that you can purchase. I did the 60 dollar per year service and it worked out great. I don't know much about computers, but apparently there are multiple types of VPNs, some of which are easier to block. The one I paid for gave me an awesome client with a list of servers all over the world that I could connect to.
I've been using Witopia a couple months now and I've been really happy with it. Lots of server options and speeds are fast. I think it was only like 60 bucks for a year of just the openvpn service.