Varick and Canal?
Mooncake as mentioned above - the only good place I've found with lunch just under $10. My faves are the steak plate and the chicken buckwheat noodles.
Aquagrill on 6th and spring - even good for take out - I like the salmon BLT sandwich.
Snack NYC on Thompson for really delicious, filling and flavorful Greek food.
Peep does a good prix fixe $8 lunch with appetizer and entree.
When I get a hankering for pho, I walk across Broome to Mott and eat at Pho Bang.
My coworkers like Grandaisy Bakery on Thompson for a light lunch - they have thin "pizzas"
This area is not good for cheap lunches and more restaurants are closing. I need to start bringing my own lunch!
PS: Avoid Hiroko's Cafe. It looks cute but it is incredibly bland and tasteless.
i work at Hudson and Varick...not great for lunch unless you don't mind a 10-minute walk...then you can hit Chinatown, of course, or futher down Varick you get into a lot of places that serve the nearby Citigroup building.
Jin Market is your basic deli/supermarket that makes good sandwiches. It's probably 5 or 6 blocks south on Varick, red awning.
Sosa Borella is now called Estancia...but still good.
Bazzini's is good too, but again pretty far down on Hudson.
this is the kind of search that yelp excels at.
this link is for a 4 block radius:
im rarely in the 'hood at lunchtime, so the only specific recs i could give are for dinner, but they may also work as lunch
broome st bar
more upscale - may not have lunch: