In-N-Out was the first place I tried in Tempe, and has been a favorite ever since. Truth be told, I wasn't even really into burgers before I tried them, and now I'm a convert. I go there when I feel like I need a treat (pretty often) and have brought several visitors from out of town for their "must have" meal. The food is fresh, quick, and filling. I love the retro feel and friendly service and quick lines always make it a positive experience.
My favorite thing is the shake - but burgers seem to be the most popular item for obvious reasons. A double double and some fries (animal style is what most people like) is sure to make any hungry person a much more happy camper. Don't miss this place! Just go!