Remarkably effective: Albert Einstein’s Theory of Relativity in Words of Four Letters or Less. Worth it just for the mental image of Albert Einstein saying “Feh. Read this and weep.” And it manages to be a pretty lucid explanation of Relativity, though there are definitely points where you can see the author struggling to get around some ordinary word that happens to be five or six letters long. (It reminded me a bit of “Uncleftish Beholding”, Poul Anderson’s discussion of atomic theory in Ander-Saxon — that is to say, English purged of all non-Germanic words. That one’s way harder to process, but it’s eye-opening as to how many technical words we’ve borrowed from Latin and Greek.)
More on the funny side: the reason why we never hear about time travelers changing history. One of those bits of parody that would have been inconceivable ten years ago, but painfully, painfully plausible now. (Via my brother, from the online magazine Abyss & Apex.)
I thought I had a third amusing link, but it seems to have gone away. Here, have a detailed explanation of what goes on in a routine autopsy instead. ‘Cause that’s a barrel of laughs.