The roller skating scene at the end is followed by an outtake of the ball pit scene, showing Jim Parsons unsuccessfully trying to hold back laughter while saying "Bazinga!" The roller skating rink doesn't completely follow the remainder of the story so it was probably the original scene planned for after the commercial break and the extra ball pit footage was added for time or humorous content.
This is the 14th episode in the 3rd season (episode 3.14), Albert Einstein (whose name is in the title) was born on March 14th (3.14).
When Sheldon serves Howard his Bacon cheeseburger, he says it breaks two Jewish dietary restrictions at one time. The first, eating bacon, is widely known, but the second is more obscure: it's the prohibition against eating meat and milk (or any dairy product) together.
Just before the scene near the end set in the roller disco, when the atoms are shown rotating, one of the orbiting electrons transforms into the glitter ball of the roller disco.
Title reference: Because Einstein came up with the Special Theory of Relativity while working a menial job at the patent office, Sheldon decides to replicate this process when he is stymied by a physics problem.