@Bert I'm referring to AWS's replacement of Xeon 8124M CPUs back in mid 2020, and Facebook's upgrade of P4500 SSDs to Optane back in mid 2019.
Essentially what happens is the hyperscalers sell these by the palette/container to their prime liquidators, then those prime liquidators break the pallets down either into individual units to sell on ebay, or smaller bundles to sell to smaller liquidators. However, eventually they all end up on ebay and they crash the price for one particular part.
For example, those 4TB P4500 drives fell to $350 when Facebook dumped them, but 6 months later they were up to $450, and now go for about $650.
If we had a megathread, anyone who was interested could just watch the thread and know when to start trolling ebay. Otherwise we just have to get lucky to catch a post, if someone posts about it either here, or on the L1 forum, or LTT forum. By the time the news hits reddit r/homelab they'll probably be gone inside of a week. I assume between Patrick and all the other people here that talk to the hyperscalers, someone will hear about the event before the giant wave hits ebay.