There are lots of others I like... but I don't quite trust the attribution. E.g. 'In case you ever foolishly forget; I am never not thinking of you' are lovely words with a nice rhythm that apparently belong to Virginia Woolf. I'd like her to have said them... but when I tried to hunt down the exact source of them in her writing the trail went cold (I'm going to keep looking though).
Ditto to: 'And those who were seen dancing were thought to be insane by those who could not hear the music'. I like the sentiment, but this quote is attributed to Friedrich Nietzsche. They might be his words but, from what I've read about him, I'm not sure they're a very Nietzsche-ish thing to say. If anyone knows otherwise though, then do let me know.