http://fi.github.com/pricing.html
I'm not trying to have my cake and eat it too -- I recognize that there's a different risk profile to outsourcing hosting of any service compared with doing everything in-house. I just want to make sure I'm not veering too far off the tracks in this case.
How about $999.99 (same as Adobe Photoshop so it should only require middle management approval)? What if you got a box like the yellow google search box (it could be called that the "premium version")?
An unknown factor in all this is how many companies would be even interested in buying a github server in the first place. If it isn't that many the costs might be too low to sustain development. I am betting that for the GitHub guys it makes a ton of sense for them to sell the private small accounts on github (and only manage/fix 1 github version). and for the big guys sell them a big package.
I'm guessing that's not going to happen, so I suppose our options are the status quo, host in a less-conspicuous location and manage our own security (as best as one can in a hosted environment), or go with the crowd and seek safety in that quasi-anonymity.
If your and/or your partners need some help putting your mind at ease about hosting your code with us, feel free to email me directly at pj@github.com and I'll do my best to help.
Presumably, the amount of proprietary code you will manage will only increase over time, perhaps remarkably so. It would be somewhat reassuring if I saw something that indicated that you take this stewardship seriously, rather than tossing off "best effort" one-liners.