Open 24 hours on week-ends, ample seating area (good for studying or hanging out and chatting), very welcoming clientele, and broad selection of coffee drinks, non-coffee drinks, and desserts, fruits, and random snacks.

The coffee isn't great but not terrible either. The Wi-Fi, while free, is fickle. 

One of my two favourite coffee places in Tempe (other is Cartel off University & Ash).