Sometimes while roaming the stores you will come across something you "just have to have!" It isn't on sale, you don't NEED it, you just HAVE to have it. At times like this, it can pay BIG time to hit your pause button.
Leave the item on the shelf, walk out of the store empty handed, drive home and THINK about it. Give yourself 48-72 hours to mull it over. If you still HAVE to have it, at LEAST comparison shop before going back to get it. Chances are though, during your pause time, you will at least talk yourself into waiting until you find it on sale... you might even find that you didn't really HAVE to have it as much as you thought you did. :)