The Original Hamburger Works is one of my fave places to grab a bite. They have enough room to ensure that you'll always [well, ALMOST] always have a place to sit, the decor is muy retro/college hangout/rustic ambience and there's lots and lots and LOTS of burgers from which to choose.
You can even see your burger being cooked if you want--and no, none of the burgers have been sitting and drying out to year-old cow-patty consistency, which is another bonus. And there's a great variety of burgers, too!
And these folks are generous in the community, too--one year, they donated one whole day's worth of revenues to the family of a Phoenix police officer who had been killed in the line of duty.
And best of all, it's another local business, which all us Yelpers need to support!