Only just now learned about let else. Am I missing anything else?

I've been using rust for a year or so, and I'm pretty sure I've read most of the rust book, but still it took me until a week ago reading a SO answer to discover the 'let... else' construct.

I don't think it was in the "everywhere you can use patterns" section of the rust book, so now I'm wondering if there's any other new or niche constructs that you know about that a newer rust developer such as myself might not?

Cheers!