You're either confused or the details have changed since you looked at it 8+ years ago.
The address space for sale is 32-bit. There is also a 128-bit space that is free
Actually, it's just a 128-bit address space (so I was wrong about it being 64-bit, but this just makes the problem that much worse). Parts of this space are divvied up IP-address style into 96-bit-wide blocks (and some other parcel sizes as well), so that carves out a 32-bit sub-space. But no matter how you slice it, the fact remains that they are selling a digital asset at a valuation that exceeds the total economic output of the known universe by several orders of magnitude. If that's not a scam, I don't know what is.
> they are selling a digital asset at a valuation that exceeds the total economic output of the known universe by several orders of magnitude. If that's not a scam, I don't know what is.
But they're not. There are 2^32 planets. A planet is the minimum unit of personal identity and is meant to correspond to a "responsible adult human". Within a planet you can have 96 bits of sub-identity, if you want to have things subordinated to your own identity (e.g. your IOT stuff, your phone, your router, your car, your kids, whatever). No one is buying a 128 bit identity.
You can buy planets right now for $10-$20 on opensea. $20 * 2^32 is about 10% of the annual military budget of the United States, not several orders of magnitude larger than the total economic output of the known universe.
OK, so the market price has gone down since I last looked. Still, even at $10, that's still a valuation of $40 billion. That's in the same league as Dow Chemical and Capital One. So I very much stand by what I said above about fools and their money.
https://urbit.org/blog/the-urbit-address-space/