Facebook has an agreement to buy OculusRift for $2 Billion.
They'd want a multiple of that to sell it. Let's say Zuck is feeling generous and decides to let it go for $3 Billion.
How many people are on HN? Compete.com says 200k uniques per month. So let's say you got every single person who visited HN last month to pitch in. That's $15,000 per person. Of course, not everybody would pitch in, and not everybody could afford to. Let's say 10% of the people could afford it. You've got $30 million, you're not even close. You'd need each of these people to contribute $150k.
This is, of course, that lots of people feel strongly enough about buying Oculus Rift, and that Zuck would be willing to let it go for $3 Bills.
In the end, would it even be worth it? Why is it so important that Facebook not own Oculus Rift? Clearly they aren't the only VR in town?