In order to seek out double entendres on Twitter, I grabbed any response tweets which mention "oo-er missus", "fnarr fnarr", "Finbarr Saunders", "that's what she said" or "is that a euphemism?", and then loaded the tweet they were replying to.
Below are the live(ish) results, or click here to see some from the archive. Whilst there are several filters in place to improve the hit-rate, loads of people seem to think fnarr-fnarr means posh laughter and I can't really filter things like that out.
Note that whilst safe search is on, it is unfiltered, so scroll down at your own risk.