I've been living in Paris for 3 months and lurk on this board often. There are always wonderful discussions of all the traditional, trendy and and star-blessed restaurants, but I wanted to start a thread on cheap haunts and holes-in-the-wall.
Here's my (very short) list of bonnes addresses so far, most of them passed down from friends who have sadly returned to the US. Please add your own favorites!
Lao-thai (13th, not sure if that is the name -- it's at 161 rue de choisy) - great laotian, thai and vietnamese dishes -- never more than 14 euros per person with beer.
Pho 14 (13th, also on rue de choisy) -- for pho (vietnamese noodle soups)
Sala Thai (13th, 13 r Frs d'Astier de la Vigerie) Delicious thai. 18 euro menu -- a *lot* of food.
Istambul pizza (10th, rue st. denis) for kebabs and delicious turkish pizza.
Wabosso (6th, 6 rue de ciseaux) decent korean bibimbap, nice to find in the touristy and expensive 6th.
Aigre Doux (3rd, 59 r Gravilliers) -- Iraqi food. The entree is not so good, but the plats (I had a kebab with eggplant) and the desserts (fromage blanc with date syrup) are delicious. 12 euro dinner menu, all wines under 10.
L'as du fallafel (4th, 34 rue de rosiers) felafel, of course. the best. I want one now!
Still in search of a fabulous lebanese restaurant, the perfect couscous, an excellent senagalese, etc....