Rebecca Greenfield, about passwords in the Atlantic Wire,
"General Internet thinking says the best way to ensure online safety is to pick different "strong passwords" for all your Internet selves and then change them often. That, as this XKCD comic illustrates, is exhausting and often counterproductive."
Click through and read the whole story. It will save you time, aggravation, and a lot of clicks on the "forgot my password" button.