One hundred dollars doesn’t go very far these days.

But for Facebook co-founder Mark Zuckerberg, a C-Note was the key to cementing his control over the social networking phenomenon.

As we learned last week when Facebook filed its prospectus for a $5 billion initial public offering, Zuckerberg has the voting rights to shares owned by some of Facebook’s biggest stakeholders, including venture capital firm Accel Partners, Digital Sky Technologies and former Facebook President Sean Parker.

In an amended filing on Wednesday, Facebook provided a little more color about the agreements that contributed to Zuck’s controversial control of 57 percent of the company’s voting shares.

Most intriguing was the price that Zuckerberg paid each of the various shareholders in exchange for handing him their voting rights: $100 in cash.

That’s not a typo.

One hundred bucks may seem like a pittance for such an important right. But it’s possible that the $100 payment was merely a formality, and that forfeiting voting rights to Zuckerberg was the real price of admission for (the raging horde of) investors seeking to buy into Facebook.