Sheldon says that the money is not important. In an episode of The Big Bang Theory (2007), Penny finds a drawer full of paychecks he never cashed because he was saving them for something important he might want later.
Dr. Linkletter gives Sheldon an autograph from Richard Feynman which was part of a restraining order and Sheldon says it's an ingenious way of getting them and that he'd have to remember that. In The Big Bang Theory (2007), Sheldon says that he has a collection of restraining orders from famous people and is shown getting one from Stan Lee in The Excelsior Acquisition (2010). The other people who took out restraining orders against Sheldon were Carl Sagan, Bill Nye and Leonard Nimoy.
The movie poster in the video store shows a fake movie called "Elemental". The actor listed on the poster is Colin D Irwin. Colin D. Irwin is a production designer for the show "Young Sheldon".
Winston Story, the man who comes into the video store looking for Die Hard (1988), was in Brooklyn Nine-Nine (2013) playing the lookalike to Detective Charles Boyle. The movie was referenced many times during the series and in one episode Charles incorrectly says the catch phrase John McClain is known for, that Meemaw didn't want to say.
To those thinking the usage of the word "hoo-hah" was anachronistic due to the time period during which this show takes place (1993), the word had been in use since at least the 1950s to describe a woman's vagina when such talk was verboten in large circles.