Red Emma's has delicious vegan and vegetarian food, as well as very tempting hot and cold beverages — including beer and wine (a more recent development). Their prices are pretty economical, ranging from a hearty $3 side dish to $7 sandwiches and salads. They also include a daily $5 special. My personal recommendation for a cheap, filling snack is the Black Bean Bomb (their bagels are perfect — chewy and flavorful). For a $7 meal, I recommend pairing their weirdly good vegan Mac & Cheese with the vegan BLT. For coffee, start with their "Red Emma's Roast." The only improvements to the food/drinks I'd suggest is to double the amount of tofu in the Bánh Mì Salad/Sandwich… and perhaps offer a nondairy espresso Affogato in the summer time!
This newer version of Red Emma's is kid-friendly and wheelchair accessible. A lot of people seem to use Red Emma's for small meetings, study sessions, and quiet hang outs. Red Emma's is also the home of the Baltimore Free School, so you might want to check out if a class session of interest to you is going on while you're there. Lastly, it's worth mentioning that Red Emma's is home to Thread Coffee, an ethical coffee collective that roasts coffee right in the cafe!
Cons: more tofu in the Banh Mi, please!