In the scene where Jo is polishing her mailbox, the name of the street is Coriolis Loop, referencing the French scientist Gustave-Gaspard Coriolis, who discovered that an apparent force that as a result of the earth's rotation deflects moving objects (as projectiles or air currents) to the right in the northern hemisphere and to the left in the southern hemisphere. The Coriolis force is also important in ballistics which correlates with Jo's chosen occupation.
References Doctor Who: In the scene where Lupo is polishing her mailbox, Zane says "Didn't know you were building a Tardis house" to which Jo replies "A what?" Zane then says "Bigger on the inside, tiny on the...never mind."
Popular songs played (or referenced) in this episode include: "Get This Party Started" (Pink), "Burning Down the House" (Talking Heads), "I Melt With You" (Modern English), "I Shot the Sheriff" (Bob Marley and the Wailers), "Why Can't We Be Friends" (War), "Bad Boys" (Inner Circle), "99 Luftballons" (Nena), and "Eye of the Tiger" (Survivor). The song "I Melt With You" was originally performed by 80s pop group Modern English, but to fit with the world-stopping plot device, a 2005 cover of the song, re-titled "Stop the World and Melt With You" (performed by pop-punk band Sugarcult) is used. This version was used in place of the original most likely for copyright reasons.
Kaven Smith and Felicia Day have work together in the past in Red: Wererewolf Hunter (2010)
In the scene where Fargo is getting his itinerary from Larry, the first appointment of the day is with Dr. Elle Wood. Elle Woods is the name of Reese Whitherspoon's character in the Legally Blonde franchise. Her character is known for being smart without sacrificing the other qualities of her quirky personality - definitely the qualities of a Eureka resident.