Beijing Cafe is like the mellow cousin of a gaudy chinatown hole-in-the-wall that moved to a quiet nook across from Marsh Plaza. It seems to cater to BU students with its central campus location, cheap food, delivery service, and a considerably late 11pm closing. 
Though they get a lot of delivery calls, I highly recommend eating in the restaurant. A waitress there claims that they get swamped during lunch and dinner, but I have never seen more than three tables occupied. It truly is like a sanctuary --quiet and intimate. Somehow the management figured out that you do not need a fish tank, flashy zodiac placemats, or chinese calendars everywhere to have a really pleasant chinese restaurant. 

- YUM photo via Huriko S on Yelp!
I could not tell you how authentic the food actually is, but the dishes are so fast, so delicious, and so cheap that I never really paid attention. The lunch specials will fill you up for $5-6, and the dinner specials for $7-8. The menu has all the standard items (available on their website), but they are listed in English so you actually know what you are ordering. If you can't seem to make up your mind, go with the General Gao's Chicken dinner special with crab rangon and fried rice; they can make it in like, 3 seconds. So, if you are really tight on cash and need to hide from the Comm. Ave. Runner, you can duck in for a $2-3 dish of rice, and you will get a free fortune cookie with your bill. Go figure.

Eat at Beijing at 728 Commonwealth Ave