The SOPA/PIPA Protest
The following is a list (woefully incomplete) of sites that took action against SOPA/PIPA:
Google (blacked out their logo)
Slashdot (blacked out their logo)
XKCD (Protest Comic)
WBAI Radio (CSS switch: Content blocks in reverse video)
I Can Has Cheezburger? and the Cheezburger Network (Banner)
TV Tropes (Banner)
EFF (Banner & CSS Switch)
The Tor Project (Censor bar across site)
Craigslist (Main page blacked out. Banner on regional pages)
Ars Technica (CSS Switch & Banner)
Not Always Right (CSS Switch & Banner)
Reddit (12-hour outage, 8AM-8PM Eastern -- US Workday)
Questionable Content web comic (Special Comic)
The Mozilla Project (12 hour outage, 8AM-8PM Eastern ; Firefox start page made black)
English Wikipedia (Offline)
2600 (and various local 2600 groups) (Offline)
The Oatmeal (Offline & Funny Picture)
SMBC Comic (Comic blacked out)
Explosm (Site blacked out)
Wasted Talent (Site blacked out)
Wordpress (Main site blacked out)
Nyan Cat (Site blacked out. No Nyan Cat.)
…and of course bsd-box.net, which was offline.
This list is woefully incomplete. It represents a few sites I thought to look at yesterday, plus one or two other people told me about.
Draw your own conclusions about how the internet feels about this legislation.