I use Op/Tech for all my cameras and binoculars.
By default, I carry the camera with a strap. If I know that I will be carry the camera for the whole day, then I also wear a harness. The connect/disconnect feature mentioned in pbo's post makes it a snap (yes, pun intended) to move the camera from the strap to the harness. My neck is forever thankful.
If I'm carrying a backpack, I can easily attach the camera to the backpack straps.
Once in a while, I need to carry two cameras. The Reporter strap makes it possible. At $17, who can resist? (You don't have to carry two cameras with it, BTW):
Op/Tech Reporter Strap
Personally, I'm not a fan of camera strap with big company name on it.