Robert Rodriguez

DVD releases of his movies always include a do-it-yourself/behind-the-scenes features on the movies entitled "10-minute Film School" (although they are rarely actually ten minutes). Beginning with the disc for Érase una vez en México (2003), he has also begun including "10-minute Cooking School" to show how to cook the trademark dishes his characters dine on.
Frequently sets his films in Texas
Frequently begins films with a scene where a supporting character is talking to another supporting character about the main character (See: Pistolero (1995), Del crepúsculo al amanecer (1996), Érase una vez en México (2003)).
Characters getting shot in the hand (See: El mariachi (1992), Del crepúsculo al amanecer (1996))
Over-the-top and surreal action scenes

Close friends with Quentin Tarantino and Kevin Smith. Often the three will be among the first to view each other's films and offer their feedback.
Salma Hayek is his children's godmother.
Directed parts of the scene in Tiempos violentos (1994) where Quentin Tarantino appears as Jimmy. (Rodriguez was uncredited for his directing.)
Has resigned from the DGA twice. The first time was so he could directed the non-guild Cuatro habitaciones (1995) with Quentin Tarantino and two other directors. The second time was in 2004 when he wanted to give Frank Miller a co-director credit for La ciudad del pecado (2005). Other notable DGA "defectors" include his close friends George Lucas and Quentin Tarantino.
Edited El mariachi (1992) at a public access station in Austin, Texas. He edited from late at night to the early hours in the morning, because the time was cheaper. However the station would often close up, setting the alarm; this meant he would have to stay at his editing bench for eight hours at a time without restroom breaks.

I didn't want Frank [Miller, creator of the comic "Sin City" and co-writer on the film] to be treated just as a writer because he is the only one who has actually been to 'Sin City'. I am making such a literal interpretation of his book that I'd have felt weird taking directing credit without him. It was easier for me to quietly resign because otherwise I'd have been force to make compromises I was unwilling to make, or set a precedent that might hurt the guild later on. -- March, 2004 in response to why he left the Directors' Guild of America just before the filming of La ciudad del pecado (2005)
I always consider Salma [Hayek] for my projects, even for male roles.
Video technology puts filmmaking back in the hands of the people. That's how I learned how to make movies - making movies at home.