With my girlfriend and two friends in the grottiest pub in the town. We were drinking and someone started joking about marriage proposals. My girlfriend said I would be too scared to think about marriage. I said that was rubbish. She didn't believe me. This started to attract some attention in the bar. While we were talking I slipped my keys from my key ring and used the metal ring fro it to ask her to marry me. She asked me if I was serious. I said I was. She said, "do it properly then, down on one knee!" I did. And she said yes with everyone in the pub watching. Everyone cheered. People came up and congratulated us throughout the evening. I bought her a proper engagement ring a few days later. We were married the next year.