I've done some things in my time that make me think my mind is going. Yesterday, I was boiling water on the stove for a pot of tea. I got online, watched an episode of Sanford and Sons, talked to a friend on the phone... 2 hours later, I remember about the water on the stove. Of course there wasn't any left, but at least I didn't burn the apartment down.
I've also added dirty dishes to a clean dishwasher, and accidentally taken "clean" (looking) ones from a dirty dishwasher.
A few days ago, I was doing the marketing. I parked my cart to look at some produce. Went back to my cart, threw the carrots in and started merrily on my way to the meat department. A few seconds later I hear a lady screaming, "Coos me. Coos me. Mira, Mira!" She pointed down to the cart... I had taken her cart WITH HER PURSE in it by mistake... mine was still sitting where I'd left it, with only a loaf of bread in it. She had a few other choice words for me, but they were all in Spanish, so I couldn't make them out. She must have thought I was trying to steal her purse. Can you imagine if she had had a child in the cart and I started prancing off with it!
I've done lots of other things... but my memory is so bad, I can't think of them!