Trying this out, based on a thread in game discussion and my own experiences in the past having lost games.
What is HB Archive?
Just a hard drive sitting in a cupboard in my room. Pretty unprofessional, but pretty safe.
You supply me with a download link to your game and I downloaded it, scan it and make sure it's OK, and save it to the disk. That's it.
Why is that useful?
I have lost games due to switching PCs often, losing websites, MegaUpload going down, and so many other things. Hell probably half my RM life is now lost.
Your games are kept indefinitely. They don't go down because hosting isn't paid. They don't go down because you lost your laptop on a bus. They don't go down because you botched an update and wiped your PC.
So people can download them from you?
No. It's just a storage service, with retrieval requests, but not in the sense of a website such as MegaUpload. It's a one in one out basis.
How do we retrieve games then?
Your games must have been released to the public, with the expectation that "once they're out there they're out there for good". As such, if anybody asks "what happened to Master of the Wind?" and it's in the archive, it's sent to them (encrypted of course if that's how you sent it out in the first place).
So... In summary?
Basically, it's just somewhere to store your games as a backup and last resort in case All Is Lost. It's happened so many times over the years.
I haven't quite set it up yet, and don't have all the details, but pretty much any game under 100mb will be accepted, with games over that side accepted providing they have taken all necessary steps to reduce it's size amongst other things. Special permission will definitely be needed above half a gig.