Depending on what you're trying to do, you're going to want to get a dedicated Fiber Optic connection. Cable, DSL and even T1 will probably not cut it at all. x10 is in fact running servers inside of datacenters. Each server would have a 1Gbps Ethernet port, with the datacenter having 10Gbps+ of Fiber Optic bandwidth with several peering points.
Really, the cheapest way to run your own server would be to buy/build a server and colocate it in a datacenter nearby you, or of course rent a dedibox/VPS from someone. But if you do want the extra bandwidth in your home, look into companies like Cogent and Level3, and other Tier 1 providers. Here at my home, I can get a dedicated fiber line for $5 a megabit (upload and download) plus payment for the fiber line to be ran from the fiber cable running to the Telephone/DSL remote to my home (telco fiber for remotes, should be able to use it for business purposes) and the equipment such as the ONT. Obviously the reason I can get fiber so cheap is because I can get it from Cogent, and because I'm near a major exchange point for their network, and fiber optic cable is within walking distance of my home. Though yet again I'm in the US so things may be different.
But really the only company that I can see that will supply you with anything would be Bell, and even so, they'll probably put you on their GAS network which will most likely still have throttling on it, unless you live in a major internet exchange such as in Toronto, then you might be able to get other companies such as the Toronto Internet Exchange company to give you fiber.
May I mention though, if you're running something super light, your upload right now should be just fine. Back when I first started my site, I ran it off of 768kbps download/128kbps upload on a DSL connection before I boosted the line to 3Mbps download/768kbps upload, and later on to a provisioning of 7.1Mbps download/1.5Mbps upload (on x10Hosting at this time) with an upload double of where it should be. My ISP does state in their TOS that servers should not be ran on the connection, however my ISP unblocked port 80 a few months ago (all ports are WIDE open now!) and they run their own server via the modems on their newer modems now, and since I run servers all the time on my connection, I'm pretty much safe to say that they don't care. I haven't heard a peep out of them in the 4 and a half years I've had DSL here, and they haven't done anything to my line as well.