49. Moonraker: "I Think He's Attempting Re-Entry Sir"
The older Bond films are full of sexual innuendoes and most of them are absolutely cringe-worthy (a moment from Tomorrow Never Dies where Moneypenny (Samantha Bond) makes a "cunning linguist" joke when Bond is in bed with a languages professor is maybe the nadir of this), but there is one enormous exception.
This ending gag from Moonraker is genuinely hilarious and there's an argument that it could be the funniest scene in Bond history.
After saving the world, Bond (Roger Moore) and main Bond Girl Holly Goodhead (Lois Chiles) are getting down to it in their space shuttle... but unfortunately their superiors get a video link patched through (and it's apparently patched through to the White House and Buckingham Palace too!).
Frederick Gray (Geoffrey Keen), the foreign minister, exclaims in disgust "My God, what's Bond doing?!"
And Q (Desmond Llewellyn), who is looking at the diagram of the flight path and is unaware of what's happening in the shuttle, replies "I think he's attempting re-entry, Sir."
Crude... but brilliant. Regardless of the issues with most Bond innuendoes this joke is genuinely hilarious and doesn't feel overly smutty like many similar Bond gags did.