Noise and desaturating your photos can give more feel and add a little timeless'ness (if there's such a word) to your photos. Bear in mind of course that the photo you took, must meet the criteria in the first place in terms of composition, lighting etc. Don't simply whack any photos and apply the following actions to them.
Here are some simple steps to achieve this desired effect :
Step 1 - Desaturate your photo to your liking
Step 2 - Add a slight tint to the photo (be it bluish, sephia'ish or whatever 'ish you want)
Step 3 - Add a little noise to it in the "Filter" -> "Add noise" function
Step 4 - Add a little vignetting
Some of the photos you see in this posting has been done up using these simple steps. Hope you enjoy the article. Adios :)