I frequently use my Ancestry.com for information. And this afternoon, I had a nice surprise. On the person I was checking, the 1940 Census index was available. That is in NY State. It is the first one I've found and it was great to find. I immediately added it to his page and copy and pasted the names in the house hold and added his occupation. This is added effort on people that I consider important in my family tree and branches, but it is great to later be able to find at a glance where they lived on each census as well as who was in the household. It makes for as complete a picture as I can get at a glance.
Another neat addition with the 1940 census is that the family you are seeking are highlighted in colors so they are easy to follow across the page.