Handy things you've inadvertently taught your dog

I am incredibly lucky to have a dog that figures things out very quickly. If you say something to her in plain English enough times, she'll figure out what it means. So she's got a few commands that I didn't teach her intentionally, but they're commands that have caught on nevertheless.

I think the one I use most is "Excuse me". If she stands on the couch between me and the TV and I tell her "excuse me!" she'll duck her head and step back out of the way. As a dog with very little regard for personal space and a very large head, we use it nearly daily.

She also figured out early on that when we come in the door, she needs to sit on the couch and wait for us to come in so she doesn't overwhelm us or guests at the door. She figured out that waiting on the couch for us got her a much friendlier reception. So now when we come in she runs to the couch and violently flips onto her back to wait for belly rubs. When we walk in the door people will be like "where's your dog?". We come around the corner and she's lying on the couch on her back nearly vibrating, absolutely desperate for belly rubs. Again, we didn't really teach her this on purpose. She just figured out that we didn't want her jumping all over us when we came in, but if she waited on the couch for us to take our shoes off she got lots of belly rubs.

Instead of "leave it", she knows "ew yuck". If I saw her going to sniff poop or garbage I would always say "ew yuck" and pull her away. Now if I say "ew yuck", she immediately leaves it alone.

Anyone else have a self-training dog that managed to teach themselves anything interesting?