I changed firms two weeks ago and have literally been working 12 hours a day. My new (temporary) office is across from the Silver Diner on Rockville Pike. After many meals at SD, I can easily report that it is some of the worst food I have ever had, perhaps surpassed in badness only by the fake, kitchy decor. There is no reason to ever go here anytime of the day for any meal or anything else. Frankly I am only writing this post because I have "post"-withdrawal symptoms.
So...If you ever find yourself at the Silver Diner despite my urging to steer clear, I recommend the Egg Salad BLT Sandwich. It is dry as a pile of fall leaves (for some reason, everything in this place tastes dry), but it is reasonably fresh, reasonably filling, and reasonably cheap. With a cup of coffee, it will sustain you until your next meal which hopefully will be somewhere else.