I keep finding these when I least expect it and they've been fantastic every time - it usually means whatever I'm trying to automate is 90% solved for me.

Scraping recipes from the bbc, flight reservations from my email, etc. If something includes schema.org/RsvpAction it probably needs to be actioned, if something contains schema.org/DiscountOffer it can probably go in the Noise folder.

If someone starts sending spam containing flight reservation meta I'm going to be so sorely disappointed in the human race.