If you're having cold feet on your passport/visa photo there's a shop on NE corner of 40th & Lex that'll do passport photos in 5 mins for $10 bucks! (look for the American Airlines storefront)
Really efficient and organized. Be prepared to wait a bit and pay attention to your number being called (they'll skip you over if you don't run up there immediately), but I was really impressed.
Went early in the morning so the service was quick but it was also rude. I came during the World Cup and was not-so-nicely told to come back after it ended since my trip is in August.
Service is swift and inhuman at the tourist visa window so be prepared to run up to it as soon as they call your number or they will call up the next number in less than 10 seconds.
Don't wait until the printed date on the slip to pick up your visa. If it says ready for pickup on the online tracker you can get it & they don't even look at your assigned date.
Not sure how all these folks had such great experiences - they are understaffed and do not honor their posted hours. As of 8/1/14 they are processing visas by appointment only. Come back then!
Money order for visas- don't get a Duane Reade one for Moneygram, they /only/ take Postal Service ones. Meaning yes, you have to go to the Post Office. On 43rd bt 5th and 6th.