My husband and I will be going to NYC for a weekend in 2 weeks. We both have been there many times before and are looking for something unique to do.
In Chicago, we took an architectural tour that was quite interesting; are there any similar tours in New York City? If anybody knows of a company that provides these tours, I would appreciate their name and any other information.
Thank you!

You might check out bigonion walking tours. They do a great job. Not sure if any of them focus exclusively on architecture, per se, but they usually focus on neighborhoods or eras in history.

There's a free, 90-minute walking tour of the Grand Central area that focuses on history and architecture--every Friday at 12:30. I thought it was pretty interesting and not dissimilar to the CAF walking tours in Chicago.

http://www.grandcentralpartnership.o..._free_tour.asp

Not the best season for walking tours (many are suspended for the holidays) but, in addition to the good suggestions you've already gotten, here are some other ideas
>the Municipal Art Society gives tours. Not sure whether any will coincide with your visit.
http://www.mas.org/calendar.php
>Food tours are very popular. In addition to bigonion.com mentioned above, http://www.foodsofny.com/ does some.
>there's a free walking tour on Sunday mornings of the lower east side. Group meets at Katz's deli at 11 am
http://www.lowereastsideny.com/lesvisitor.htm
>the nycvisit website has a calendar that allows you to search for tours (or other things) by date. Assuming you're coming the weekend of the 15-17, here are their listings.
http://www.nycvisit.com/calendar/eve...cfm?pagePkey=9

The Friday Ny Times lists many walks and tours available.

Have you been to the Tenement Museum on the Lower East Side? If not, I suggest a visit.

www.tenement.org