Flickr

I love my Flickr account.  I've had it for a little over a year now and it is very easy to use and fun to scroll through.  It was a bit of a bummer when I realized for what I wanted to do I'd need to pay...but after that bump in the road I figured out how much fun it can/would be.

For research, the answer is pretty simply.  With an ability to search hundreds of thousands of photos for all over the world, it provides a way to search photo content for posters, projects, papers, anything!  Plus with Flickr's settings, almost anything is allowed use as long as you give credit to where it came from.  I've noticed lately that Google image has cracked down a bit on copy/paste abilities, but with Flickr you can find amazing photographs of almost anywhere you can image. 

Also, Flickr allows you to contact other users so if you want to be extra careful about copy right laws, you can always contact the person for permission. 

Another great research tool would be the ability to search what some place looks like.  Say your reading a novel set in a rural village in China.  Most of us have never been lucky enough to have visited China and the descriptions may seem very...well...foreign.  By searching posted pictures of real like action in places such as a rural village in China, we have an ability to gain better understanding of the subject someone is studying. 

Flickr and other photo sharing sites are another way to connect and share our experiences.  Friends who have gotten married have posted all their photos to a Flickr so that guests who weren't able to attend can still see all the great moments. 

The world is getting smaller.  Now, even though you may have never ridden on the back of an elephant, or swam in an African waterfall, or been up close an personal with deep sea creatures, photo sharing sites let you experience what other's have all over the world.