turn signal light swap

hi ive seen some pictures where people have their turn signals on all the time and have the corners off. how are they doing this? or is it possible to hook up my turn signals to where they are on all the time but blink when the blinkers on? thanks for the help.

Search.

http://www.g2ic.com/tegtips/lighting/3.html
http://www.g2ic.com/tegtips/lighting/7.html
http://www.g2ic.com/tegtips/lighting/24.html