The number on August's door is 2. This is a sly nod to the film connected to August's identity, the second animated feature produced by Disney.
The lunch box that Regina brings Henry is a TRON lunch box. Once Upon a Time (2011) creators, Adam Horowitz and Edward Kitsis, wrote the screenplay for Tron: Legacy (2010).
When Pinocchio comes out of the tree in the real world, he is startled by a airplane flying overhead. The plane goes by very quickly but it very much resembles a plane from Oceanic Airlines (from Lost)
When Regina and David go to her house, you see that her house number is 108. That is one of the 'magic' numbers from the show Lost. There were 108 passengers on the plane and Desmond needed to key in 108 in the computer every 4 minutes.
August told Emma that he woke up at 815 AM, which is another number from the show lost (Oceanic Airlines Flight 815)