These shows all take inspiration from the comics that came before them, and all like to take some time to pay homage to that. In fact, with most of these shows, pretty much anytime you hear a reference to a specific street, it's worth checking out because it probably calls back to one of the artists or writers who worked on the comics.
So, for example, in Supergirl you've got 6th and Sprang, which refers to artist Dick Sprang, who began working on Batman way back in 1941, although he never actual received a credit due to a clause in Bob Kane's contract. There's also Otto Binder bridge, named after Supergirl's co-creator.
Over on Arrow, there are the likes of Adams and O'Neil, which refers to Dennis O'Neil and Neal Adams, and also Adams and Infantino, the latter referring to the man who helped create Barry Allen.
Over on The Flash, there's the likes of 4th and Kolins, for artist Scott Kolins, and Waid Blvd, for writer Mark Waid. In Legends of Tomorrow, Martin Stein is revealed to be a winner of something called the Carlin Award. That's named after Mike Carlin, a long-time DC editor. Basically, if there's any sort of name thrown out there in any of these shows, it's probably an Easter egg.
NCTJ-qualified journalist. Most definitely not a racing driver. Drink too much tea; eat too much peanut butter; watch too much TV. Sadly only the latter paying off so far.
A mix of wise-old man in a young man's body with a child-like wonder about him and a great otherworldly sensibility.