See? No! Evil!

If I was blind (and if adult onset diabetes doesn't do it, my love of bottle rockets surely will), I'd be bitter about losing my sight and having to learn Braille - and as a result, I'd also really resent anyone who still had their vision. But it would definitely ease my pain if all Braille reading material included hidden jokes about people who weren't blind. It'd be a nice, secret "Fuck you!" to the rest of the eye-using world. And how would they ever find out?
It'd soothe my tortured soul to open up my Braille edition of "Classical Pianist Monthly" (I just assume that after my blinding, I'd take up classical piano) and read a delicious bon mott like, "It takes two 'i's to make an 'idiot!' (you know - "i"s to "eyes" - it's more of a verbal gag, but you get the idea).
And for the same reason, I think people who aren't deaf should be taught the wrong meaning for some sign language. That way, deaf people can have the last laugh when non-deaf people say goodbye to them by unknowingly signing, "Have a nice testicle."