One of the most commonly misplaced items is the mobile phone. Sitting on a terrace with a drink it seems only logical that you don't put your phone back in your pocket after using it. When something attracts your attention when you're ready to go, chances are you'll forget your phone. In most cases it's not the loss of the phone itself that really hurts, but you don't want to lose your simcard that has all your connections on it. It takes a lot of effort to make up for a loss like this.
The place where most sunglasses get lost, is undoubtedly also the terrace. In this case, the lack of sunny days and the opportunity to visit a terrace is the culprit. We're so happy to be able to wear our expensive sunglasses, that we keep putting them on and taking them off again. Maybe to look at a pretty woman, or to make people notice us.
To lose a rental car when you're on a holiday; maybe it wouldn't happen to you, but there are stories of people who visit crowded cities with a rental car and misplace it in a parking. Just because they forgot to pay attention to the make, the model and the color. They won't notice the fact that there are hundreds or even thousands of cars in that place until they come back for their car.
Marriage- or engagement ring
Nobody will state that your life wil never be the same again when this happens, but relations have ended because of it: the loss of a marriage or engagement ring. For some reason this seems to happen to men more often than to women. When those men are married to a suspicious woman, there's no way of telling what can happen.
It may sound unbelievable, but there are actually people who lose track of their children. In most cases, the consequences aren't too serious, because there are people around who do pay attention. It may be the most important similarity between these examples: the lack of attention. Let's just hope there is no real forgetting in this forgetfulness.