When Phil slides into scene with his guitar, it's an obvious nod to Tom Cruises's famous underpants slide in Risky Business. Even the staircase is replicant in the background. The only difference is that Phil slides in from the right instead of from the left and he is fully clothed.
There are scenes from two different Three Stooges shorts featured in the movie. The first one that Becca is watching is from Punch Drunks (1935) and the second one that Crispin is watching is from Pardon My Scotch (1935).
Ben's line "I see your eye twitching!" while he and Charlie are building the swing set is a reference to Eddy Murphy's role in the Shrek movies. In the first Shrek, Murphy's character Donkey says "look at my eye twitching!"