F=ma ! Now you can accelerate horizontally and crash into a thing if you hit it fast enough, it might move!
Feel free to spend as much time as you want messing around with the examples, they'll probably break pretty easy, I didn't have a ton of time to work on them. You can find a link to my GitHub page on the About tab, and sources I used to learn the javascript and HTML/CSS I needed to get this up and running.