Chicago isn't exactly New York City or San Francisco when it comes to amazing sushi joints. I was just walking through San Francisco's Japantown earlier this week, and couldn't get over the number of Japanese restaurants patronized by ex-pats. But we do have a few gems. I think the thing they all have in common is that there is a gentleman behind the bar who has put in his time as an apprentice somewhere, washing and cooking rice; understanding the proper balance between rice vinegar and sugar and treating those little white grains with the respect and care they often fail to receive at lesser, cookie-cutter sushi joints. He knows how to purchase, select and cut his fish, and since his clientele is a shade more serious than the usual gaggle of amateurs, he spends more time slicing sashimi or making elegant, yet simple and pristine nigiri - draping his slender pieces of fish over the vinegared rice and attaching it with the slightest dab of wasabi (occasionally straight from the wasabi plant itself, grated to order) - instead of cranking out spicy tuna rolls and deep-fried godzilla/bagel/Philly/dragon/kitchen sink maki all night. I would feel confident going into any of these places, propping myself up at the sushi bar, and simply asking for an omakase, or chef's tasting menu, entrusting my meal to his whims.
4. Sai Cafe
Honorable mention: Tanoshii