If you can find it, there's an episode of the BBC comedy panel show "Unbelievable Truth" where they list all the nuts that aren't nuts. Entertaining and surprising.

The bit we eat is usually a seed or fruit - the shell encasing it is a nut. At least, that's what I understood.

And certainly an episode or several of the BBC's (television though, not radio) QI too.

Series 21 episode 5 David Mitchell's rant is splendid.