From this post, which I keep updating.
First and foremost, Calcutta Indian Food in Ximen has moved. Go to the old place at #126 Kunming Street (follow Chengdu Rd. from MRT Ximen and turn right on Kunming), then keep going to the first light. Turn right and across the street from Holiday KTV there is a building called "U2". The new location is in the basement food court, towards the back. The food is still the same great stuff. They have Kingfisher!
Secondly, we tried Mayur Indian and it's great, but dosa is no longer on the menu (not enough demand).
Finally, I found a new place - south side of Ren'ai Road, beween Jianguo and Fuxing (near Howard Hotel). Haven't tried it yet - but will go soon and report back. I'm currently doing "research" by eating at every Mexican/Tex-Mex place I know of in Taipei to do a post on it, but I can sacrifice one evening out to get more Indian, ha ha.