We learn that Steve Bartowski had invented and tested the original Intersect on himself, saying he did it 20 years ago. This is a nod to Scott Bakula's series, Quantum Leap (1989), which premiered 20 years ago in 1989. Bakula's character, Sam Beckett, was a physicist/computer genius who had tested the Quantum Leap Accelerator he invented, on himself.
In the season finale "Chuck vs. the Ring," the big wedding is delayed by Chuck's friends Jeff and Lester, as their band "Jeffster," performing Styx's "Mr. Roboto." This episode also features Tony Hale, who appeared as the driver lip-syncing "Mr. Roboto" in a famous Volkswagon commercial touting their then-brand-new six-speaker cassette system.