--Dosa (I prefer the Valencia location over the more stylish Fillmore spot)
--Little Star Pizza
3216 Mission St, San Francisco, CA 94110
Little Star Pizza Valencia
400 Valencia St, San Francisco, CA 94103
995 Valencia Street, San Francisco, CA 94110
Lers Ros, Burmese Kitchen, Angkor Borei.
Ideale and Nopa would set me back more than $30, as would dinner (rather than the recommended brunch) at Canteen.
3471 Mission St, San Francisco, CA 94110
Larkin Express Burmese Kitchen
452 Larkin St, San Francisco, CA 94102
Lers Ros Thai
730 Larkin St, San Francisco, CA
Pearl's Deluxe Burgers, Shanghai House, Hong Kong Lounge. All of those are under $20 most days.
If ambiance is a factor: NOPA, Fresca, Ideale
560 Divisadero St, San Francisco, CA 94117
3641 Balboa St, San Francisco, CA 94121
Pearl's Deluxe Burgers
708 Post St, San Francisco, CA 94109
Hong Kong Lounge
5322 Geary Boulevard, San Francisco, CA 94121
The Foodhoe blog did an excellent review with photos of the $9 lunch
One of my favorites in SF is 1550 where Sunday-Thursday there is a Prix-Fixe Menu with three courses $29.95. While it is a neighobrhood place, the cable car goes by it and you can take a ride there.
Not in the same league, but a good value is Town's End with a $22.95, 3 course prix fixe. They have their own bakery and the bread basket that comes with dinner is quite nice.
$22.95, 3 course prix fixe;
On Sunday, Monday and Tuesday night from 10pm - 2pm Tropisueno is servig free food with the purchase of a drink. Click on the photo of the girl in the center for details