Ribbons
A ribbon is a very simple design and yet, a lot of people order them. In fact, they're easily one of the most recognizable designs out there. This is because they're usually used for noble causes and people are more than willing to wear them to show support for the noble causes. For example, we all know that a pink ribbon is worn to support breast cancer. On the other hand, a red ribbon is for HIV awareness. There's also the blue ribbon that helps fight child abuse. There are also more complicated designs like the US flag shaped like a ribbon to show support for the troops. There are different designs but all of them share one thing - groups use them to help drum up support and they do a great job at it. This makes them very popular.