If you are that concerned, you can buy additional bandwidth for your server. Buying pre-allocated bandwidth is cheaper than emergency bandwidth, so I would look at any current usage statistics and go from there.
I mentioned that in my first post, but it would get very expensive. Basically, what I'm doing is looking at the "what if" scenario due to having a video hosting site. If it were to become popular and consume several terabytes per month, how much would that be in total billing? Say for example, I had 25 terabytes used per month, and if I had the 2,500 gb plan, that is 2.5 terabytes + the 22.5 extra terabytes of usage.
I'm just trying to play it safe and looking ahead, since I know that video hosting sites can be bandwidth hogs. So if my math is right, it's about $600 per extra terabyte? So if I hypothetically needed 22.5 more terabytes to cover that scenario, that would be $13,500?