The way I see it, you either ignore regular drops on your other characters, or you set up some sort of pixel scanner to pop up a message whenever a certain color of item drops.

Otherwise, just do a quick look when you drop an elite or a named or a boss. You still get most of the gold from quests and running over it, so in reality, maybe you're looking at only getting maybe 2-3 times the loot and 3-4 times the gold of 4 individuals, but that's still not bad for one person.