SOPA could destroy people's perfectly legitimate livelihoods:

source: xkcd (aka the greatest webcomic of all time)

(Cool stuff under the blackout I got to see for a second when I uploaded the pic: Guy in hat saying "Seriously. Don't screw with DNS. If you break this internet, we are NOT making you a new one!") 

(Bonus points: the alt-text on the website says Randall's getting blackout drunk to support the protests. Always the way to go.)

(jk blacking out seems scary. i've never done it. please don't die.)