What do you do when your parents piss you off?

I feel like I've had a lot of patience. For 17 years of my life I've put up with them fighting with each other, yelling at us to be better than what we are, for being two-faced, for wasting half the family's savings for ambitious unrealistic dreams, etc. One of the things I can't stand, however, is them trying to limit the things I am interested in. I am often doing research on the computer, whether it's on art, animal science, military history, etc. but all they see is me "playing" on the computer. All they want me to do is coop myself up in my bedroom reading books. And although I do that too sometimes it's just easier to research things online. I can't even explain that to them because some of the things I enjoy researching (like military science and history of weapons), my parents deem too violent. That is true but just because I am researching this does not mean that I will turn into a killer all of a sudden but they refuse to listen to my reasoning. Just 10 minutes ago my mom said, "If you're not doing homework get off the computer." WTF I finished my homework. I'm not even playing games, not that I even did this entire past year. I'm running out of patience and I'm afraid I'll blow up at my parents really soon. What do you guys do when your parents get on your last nerves?