I have for some time been really interested in taking photos of strangers in the street and have been involved in the 100 Strangers forum on Flickr. I managed to put together an exhibition of some of my images and titled it "Strangers in a Strange Landscape".
Some examples are below.
Brief info about "100 Strangers" on Flickr
The 100 Strangers ethos is learning by doing. It is not a race to collect 100 pictures. If it appears that you are not learning by doing, that you are simply collecting photographs of strangers, please submit them elsewhere. This is a closely moderated group. Please read the rules and guidelines. Submitted photos will have to wait to be approved by the staff before they can appear in the group pool. This will usually take only a couple of hours, please have a little patience.