Okay, so when you move you add to the mass of the Universe. I'm cool with that. And that means that when you die, you stop adding mass to the Universe because you're not moving any more (althought I've heard about people spinning in their graves, which would not only add to the mass of the Universe but create a problem with graves filling up with yarn, not to mention the question of where the wool and stuff comes from -- possibly Dark Matter). But anyway, there are lots more dead people than live people, so that means that the Universe has been losing mass for a very long time. And that brings up the question...

are we disappearing bit by the bit? And if so, how can we know?