We drove by a Pupuseria in Worcester -- on Pleasant Street, about a block up from downtown. We were going out for dinner in an hour, so we only split a pupusa, and it was quite good. Toastly lightly greasy outside, nice bean filling, and nice cabbage slaw with it. We will try to stop back for a mean next time we are in town. The people were very friendly, but I did feel a bit like a Cossack in a Sukkah.
The place is a across the street from Emilia's a fabulous middle eastern lunch place (where I have not been in years).