What have you always wanted to try? What is it that's holding you back? Is it fear? Yourself? Whatever it is, don't let it stop you. I know it's easier said then done, but it's certainly worth a try. In all reality, the only thing holding you back is yourself.
Sure, trying things outside of your comfort zone can be terrifying, but just imagine the feeling when you accomplish something new. The freeing feeling. Knowing that you finally broke out. Honestly, the best thing about trying something new is learning. You learn in the process, not only new information, but also about yourself.
When we learn new things, we are growing in the process. There is no progress when we stay within our limits. We are our only limit. If you really want something, you'll find a way. Sometimes it takes a little push to get you going in the right direction. Sometimes it may take you a little longer than others to try something, but don't be discouraged. We all go at our own pace, and we all eventually figure things out.
If anything, let this be a little motivation to at least, think about something you've never experienced. Think about what you want to do that you've never done before. Then from there, figure out how you want to go about things (if you're more of a planner) or if you're spontaneous, just go for it. Even if things don't work out for the best, at least you know that you tried, an you can pick yourself back up and try the next thing.