Take the Seibu Shinjuku line one station west from their Shinjuku (Kabukicho) terminal and you arrive in Takadanobaba, a budget foodie paradise.

The nearby Waseda University and other academic institutions guarantee that the local restaurants cater for the budget-conscious crowd.
One of my favorites in the area is a bar/restaurant where they have set up a drinks buffet. Bottles of booze and mixers on a table for a set price.

They serve quite tasty food too, so it's not purely a nomihoodai joint.