The GF and I went to this new spot just north of us for dinner last night. It is in a spot on W Armitage previously inhabited by a Mexican restaurant (the decor is an interesting blend of styles, to say the least). It's BYOB for now (the mgr said that they may apply at some date down the road).
Cool interior, very spacious, with the sushi bar placed in the center like an island, which divides the space into a more "formal" dining room and a more "casual" loungy side with a TV.
We sat in the front window, and only complaint we had was the ever-changing "mood light" on the top window sill. This cascaded blue/green/red tones on our table so our hue of our plates was constantly changing.
We started with miso soup, edamame, and the grilled Hamachi neck appetizer. The soup and soy beans were solid, but we were really impressed by the grilled fish. It was really Hamachi collar, grilled to impart a bit of smokiness. Very moist and tender, and I think about $7-8.

We ordered some Maki and Nigiri sushi for our main course.

Rock Roll (across in orange) was our favorite: tempura shrimp, tuna, spicy mayo and I think something else (it's not listed on the take-out/delivery menu we grabbed)
Mexican Maki: hamachi, avocado, cucumber, cilantro, and jalapeno chile sauce
Maguro & (super) white tuna nigiri - the white tuna was amazingly tender, like buttah!
The menu is a huge format, laminated, and reminded me of a Denny's menu due to the wide selection of items.
The service was warm and friendly, and outside of a long wait for the sushi platter (there was a big party that ordered before us) it was a very pleasant experience. Our total bill came to $61, plus tip. A solid deal, although the nigiri prices were a touch high ($3 and up per piece).
Koko Sushi Bar
2829 W. Armitage Ave.
Chicago, IL 60647
773-235-2199
http://kokosushibar.com/
- Mark
Homer: Are you saying you're never going to eat any animal again? What about bacon? Ham? Pork chops?
Lisa: Dad, those all come from the same animal.
Homer: Heh heh heh. Ooh, yeah, right, Lisa. A wonderful, magical animal.