Dawson Casting: Summer has frequently been cast as characters who are either teenagers or supposed to be teenagers. She is currently thirty, but can pull off the teenage appearance with almost unnerving ease.
Does Not Like Shoes: Summer has tendonitis in her heels and arthritis in her toesnote Not surprising, given her background as a ballerina. Ballet is a strenuous art that can mess up even the toughest feet; see Black Swan for a great example., so shoes actually are painful for her to wear. She has said that boots, specifically cowboy boots, are more comfortable for her.
I have a scar on my face from when I was shooting. I was at a shooting range and a shell flew back and burned my face, so [director] David Nutter let it show all through the pilot [of The Sarah Connor Chronicles], and if you watch you can see it all through the episode. I thought that was great because she is supposed to be human[-like]. — from IF Magazine.
Mean Character, Nice Actor: Despite playing killer robots, psychopaths, and other assorted crazy characters, she is frequently described as one of the nicest people in Hollywood.
Phrase Catcher: After an infamous incident of Summer screwing up her lines during the filming of Firefly, the other cast members - most notably Nathan Fillion - took to yelling her name as an expletive whenever anything went wrong. Nathan is rumored to have taken the tradition on to his succeeding shows including Drive and Castle.
Unkempt Beauty: She certainly seems to have this trait, as she looks more attractive and beautiful without makeup. This is especially noticeable with her characters in The Sarah Connor Chronicles and is rather striking in Deadly Honeymoon, where there are scenes showing the characters without much makeup and later with it - and the difference is amazing. With the makeup, Summer looks like a doll, while without it, she looks very real and natural.
Despite her tiny frame, Summer Glau is actually pretty well-trained in multiple martial arts disciplines. When called on to convincingly beat up people several times her size (like in the aforementioned scene) she requires No Stunt Double.
What Could Have Been: Before she met up with Joss Whedon, she was almost a Power Ranger, saying she was the second choice for Power Rangers Wild Forcenote She claims as the Pink Ranger, but that season had no Pink Ranger, only white with pink highlights.