Just a thought but given "have a computer with 1M of RAM and no other local storage. I must use it to accept 1 million 8-digit decimal numbers over a TCP connection, "
I was wondering why you can't use TCP as a form of storage, possibly many ways but latency and buffers would actualy work for you as crude storage. Not that it is need in this case but it is one form of queue that could be abused to store data.
If you go that way: mail all numbers as message subjects to your GMail account, then list your messages alphabetically.
You can 'store' data in DNS, too by, measuring response time to non-existent domains. The first lookup stores a one; skip it if you want to store a zero, the second one destructively reads it with some probability of data loss.
I must of missed that one, though good too know I'm just as sane as others out there. Many forms of storage that most forget is out there as not directly obvious. Even the display ram is usable - blame my ZX81 days for that perversion.
I was wondering why you can't use TCP as a form of storage, possibly many ways but latency and buffers would actualy work for you as crude storage. Not that it is need in this case but it is one form of queue that could be abused to store data.