Use on of the following twitter icons during Operation Blackout Twitter Op on Nov. 5th through Dec. 30th. Or use your default icon or create your own.

http://imgur.com/N9g0n
http://imgur.com/od1af
http://imgur.com/dyR0r
http://imgur.com/CtLgQ
http://imgur.com/B1n3I
http://imgur.com/sQh8d