Le Pain Quotidien opened a few weeks ago below Gold's Gym on the corner of North Fillmore and Clarendon Blvd. The restaurant is an international chain and it's name translates into "daily bread" I believe, which is fitting as it offers good breakfast treats, fresh bread, and sandwiches. I would compare it to a little more upscale Panera Bread.
The chain has received great reviews in other locales, and my first visit was also positive. Looking forward to trying out some more of their lunch menu later, especially given that their location is very convenient to Clarendon foot traffic:
2900 Clarendon Blvd
@ N. Fillmore St.
Arlington, VA 22201
M-Th: 7am-9pm
F: 7am-10pm
Sa: 8am-10pm
Su: 8am-8pm