What a nice surprise! I ducked in here to escape the Saturday crowds on Penn Avenue in the Strip District, and was pleased to see a small but bright space with Intelligentsia coffee and a Clover machine. The upstairs seating area is a nice, cozy place to hide, and the friendly staff helped me to overcome my indecisiveness.
Like many businesses in the Strip, 21st Street Coffee is not open at night, but it's a good option for some daytime coffee with serious standards.