Let's say that you're camping someone, or hiking or biking or whatever, you have a can of food you want to open but you forgot your can opener, a knife or anything that could open the can for you. Fortunately, there's this trick to make it so you can open a can without a can opener. Here's what you need:

• A can of whatever
• A cement surface
• Elbow grease
• A fingernail
tanktop optional

Basically, you just rub the lid in a circular motion until it gives you that opening for your to stick your fingernail in and peel the lid off. You better be pretty hungry to try this but, that being the case, why would you be traveling with cans of food and not bring a can opener? Either way, here's the demonstration.