Dinner tonight in E boston
Nice Chowhound handle! You've got many good suggestions here already. Let me add:
Ecco -- casual New American / upscale comfort food plus good cocktails and free parking. Probably the coolest atmosphere in Eastie; I describe it as Franklin Cafe-like.
Pupuseria Mama Blanca -- very modest-looking Salvadoran counter-service place with terrific, very inexpensive fare. Soft drinks only.
If you go to Angela's (which I think is the best real Mexican restaurant in Boston, an astonishing Poblana chef), be sure to order off the specials boards overhead, which is where the really good stuff is; the paper menu is dull. Beer/wine.
I haven't been back in a while, but I used to enjoy Carmen's Kitchen, a casual Italian-American place. Beer/wine.
Would love to hear a followup report!
re: MC Slim JB
Also love the handle, particularly as JazzFest season approaches in New Orleans!
On my last visit to Angela's, I thought I noticed that most of the blackboard specials now also appear on the printed menu. I may be remembering incorrectly. That said, everything you need to know is on the blackboards, although make sure your server tells you what the specials are. There usually are some in addition to what's on the blackboard, and although Luis never forgets, sometimes some of his servers forget to tell you about them.
el buen gusto and topacio for salvadoran
rincon limeno, el chalan, and beto's for peruvian
el jardin, el paisa, and el penol for colombian
there are also a number of taquerias (el rancho grande, taqueria jalisco), pupuserias (la frontera, la reina), and bakeries (spinelli's, cucchiello's, lolly's, peaches and cream) in the area