P.S. bangkok never fails to please. No matter who I go there with, everyone always loves it. The service is friendly and helpful and the thai decor is warm, but most importantly, the food is consistently great. The dishes aren't necessarily prepared in the typical chicago-thai-restaurant style, and the variations are always better than the standard. It may not taste like the paad thai you can get at any other thai place, but it's better here. Also, they'll prepare any dish vegetarian if you ask.
Pros: rarely crowded, vegetarian-friendly, best thai in town!
Cons: hard to find parking