There were 15 of us clustered around a not-large-enough table at CES, almost all plugged into identical power adapters. I put a rubber band around mine to keep from mixing it up with somebody else's. Turns out, I'm a genius.
Almost a month later, the band is a permanent fixture on my brick—it's proven to be equally MVP at home. No, there aren't 15 scumbag tech writers packed around dining room table (right now, anyway), but the rubber band is still pulling its weight. More to the point, it keeps the power brick from pulling its weight. Right off the table, dragging the rest of the power cord with it, yanking the MagSafe connector clean out of my laptop. Sound familiar? Yeah, we must be related, because this used to happen to me all the time.
As beautifully designed as the MacBook power cord assembly is, it has two fundamental design flaws. One is that the plug-side cord is HEAVY. Combine this with the brick's slippery shiny surface, and you have a recipe for a plastic block being dragged off a table by a cable that's slung like a catenary between the outlet and the table's edge. Unless you band that shit, in which case the brick doesn't move at all.
You're welcome, Humanity.