I took salary into account when ranking programs. I used bestplaces.net to get a percentage of cost of living compared to the city where I went to school since I knew how far money really went in that city. Then multiplied that factor times the salary at a program averaged over five years to get a "real salary", or an approximation of what my salary would be like in the town I currently lived in. Contrary to what some people say, I found significant variation in salaries among programs and it doesn't always go up in a manner commensurate with increased cost of living. For example, last year the intern salary at UTSW was like 32.5K/yr, while at Lenox Hill it was like 47k. Big difference. While New York is way more expensive to live in, most programs there subsidize housing costs as well, which makes it a bit more complicated to compare.
The real difficulty is comparing benefits. While you can easily find out what benefits you will get, it is much more time consuming to quantify what those benefits will be worth to you because you have to compare insurance costs etc in each locale. Benefits packages vary on a very wide scale, which makes it even more difficult to compare. The ability and opportunities for moonlighting are yet another complicating variable that is extremely difficult to quantify. Bottom line is that it is very difficult to get a real handle on how you will live as a resident money-wise.
In the end I don't think this should be a big factor in your ranking, but if you have plenty of time and the inclination to do the research it can help you sort out the midle and bottom thirds of your rank list. The top part should be all about where you think you will fit in and get the best training for your long term career goals.
Good luck.