A dedicated server will also allow you to do more than just host websites...you can also host video games on the server, test out software, play with server configurations blah blah blah. It is definitely an awesome system to have. The price you pay is far cheaper than what you will pay for taht same unit in your house to have the bandwidth allocated to it blah blah blah.
I sell Dedicated Servers and I can tell you that dedicated IPs are the key.
You can't get a dedicated IP with your ISP without going to a business class service and paying for the static IP address option which will be a very expensive option, definitely more than the price of one of my low end dedicated servers, and more than triple or quadruple the price of my VPS options.