Stephen King appears in a cameo role as a "cleaner" called Bachman, a reference to his old Pen Name, Richard Bachman.
When planning Gemma's hiding in Canada, Tig suggests that she "go redhead," referencing Katy Sagal's role as Peg Bundy in Married... with Children. Gemma states that she'd rather shave her head.
When Jax takes Luann to the new porn studio she is initially afraid that he is going to murder her. Jax tells her he isn't going to "go Adrianna" on her. A reference to Drea de Matteo (who played Jax's son's mother)'s character from The Sopranos.
Chibs' name dropping another movie he was in.
Chibs: I love the green! All about the Benjamins!"
A basketball player calls Kozik a "lemonheaded sucka." Hmm, didn't Kenny Johnson play a guy in a certain TV show where his nickname was "Lem," which was short for "Lemonhead"? Also His final line of dialogue, before being blown up by a landmine, was "You gotta be shittin' me", one of his Shield character's catchphrases.
When Walton Goggins, of The Shield shows up playing a transsexual hooker, his character is named Venus Van Damme. His character on The Shield twice used Cletus Van Damme as an alias.
Charlie Barofsky is a history buff, much like Peter Weller himself.
Gemma is Peg Bundy (which is funny, because before Peg married Al, she dated a lot of sleazy guys — some of which were bikers, and Gemma is more of a cruel, abusive parent than Peg ever was), Turanga Leela, or Kate Hennessy
Chibs is the Scottish groom in Braveheart whose wife was taken by the local lord on their wedding day, and Maximus' servant Cicero from Gladiator... and in fact generally That Guy from a variety of films.
Lenny "The Pimp" Janowitz is none other than Sonny Barger, founder of the Hell's Angels.
Hector Salazar is the same name as one of the Mexican drug runners trying to obtain the Cordella virus in 24, whose brother Ramon is a nutcase just like Ramon Salazar, a Spanish nut job involved with viruses in Resident Evil 4.
Stunt Casting: Walton Goggins of The Shield and Justified has a small part as the transsexual escort Venus Van Damme. Made even more amazing by the fact that it was completely kept secret until the episode aired, to the extent of pushing Goggins' on-screen credit to the end of the ep. Even the name choice was great, as his character on The Shield twice used "Cletus Van Damme" as an alias.