One of the robots ("moravecs" (amazing)) in Dan Simmons' Ilium was also crustacean formed: Orphu of Io (and his friend Mahnmut. Beat Charles to that particular weird coincidence-to-be by plus or minus a year!

It's not quite as memorable or as strong a theme as Accelerando laid down. But still quite a serendipity, imo.

Edit: oh, Charlie is down thread pointing out Lobsters was published on 2002, written 1998. Nice. https://news.ycombinator.com/item?id=48163630