Right, next time some smartypants calls gravity a force (especially a really clever one) you can smugly tell them it isn't and point them to Sabine's video which explains exactly why in painful painstaking detail.
Oh, I like it: check out the URL for this thread: it ends in 1337, which is the numerical equivalent of "leet". How gloriously coincidental is that?! Yes, Sabine is extremely good at explaining things!