If you're interested in knowing what happens when you scale up (in the USA), I recently went on a quest to move from a collection of virtual private servers to some sort of dedicated solution.
* The cheapest I found in a tor friendly fully dedicated server is 70$/mo for 1Gbps transit (via OVH)
* The cheapest 1 rack collocation I've found is 400$/mo for 1Gbps transit (via HurricaneElectric); this was substantially cheaper than most quarter and half rack colo options as well.
This cost is broken out into two things
* transit (when not using a discount network like HE) you can expect to pay upwards of $1000 / Gbit
* power (and cooling), somewhere between 10~50$/mo per amp depending on how dense you are and if you want redundant A/B power.
For not particularly dense installs on modern hardware, you can thumb about 1.5A per rack U. And that modern server is going to set you back a couple thousand as well (though you can get cheap 5year old hardware for a couple bucks if you have the power/cooling to spare.)
I'm continually surprised by how cheap VPS providers can go. Either they're massively over-provisioning, or they get really good deals in bulk; probably both.
~Mwalker