I was flying LAX - CLD on a Brazzy emb-120 once in 7A (exit); Across the aisle to 7B (exit) was a guy who's bag was way too big to be under the seat, such that any of us running out his window exit would trip over his huge bag.

For some reason, the Skywest FA didn't catch it. So as we were taxiing and she walked by, I stopped her and pointed out his bag. She took it from him and found some other way to safely store it.

He got furious with me: "Why don't you mind your own business!"

I said I didn't feel like burning to death laying on top of his dumb suitcase after having tripped on it. He shut up for the rest of our uneventful 22 minute flight.