When we first see Harvey's toad collection, the camera cuts to a further view, revealing that it's pretty large. Benjamin's going to be here for a while...
The first time we visit the joke shop. One prank involves sprinkling mite eggs into someone's undergarments, so they'll spend the whole wedding wanting to scratch their crotch, and another involves sweets filled with potassium.
The woman asking someone to help carry her baby stroller for her, and that someone carries it with her all the way to her house. Her appearance at the end of the episode she appears in implies that she was expecting that.
A man gives money to a person with a charity collection box. She puts a sticker on him. Just as he walks off, he realises that the sticker says, "Bring back the slave trade".
The Reveal that Ross was working for social services all along. Doubles as a moment of awesome, as well, after seeing how he was treated by Pauline in the previous episodes.
The graffiti on a sign outside the church, which originally said, "Salvation: Jesus is Shit!"
When Harvey and Val have Benjamin in bed after he returns, they are looking at a thermometer, noticing how unusually high the temperature. The suggestion that follows? "Try it in his mouth".
The musical number that immediately follows about where germs can be and how they both like things kept clean.