I use Pinterest. I just use it to 'pin' things I am interested in:
Books I want to read, decorating ideas, recipes, art, photography, crafts and interesting websites or blogs, the list is endless. I use it to refer to for new ideas in my art related profession
You can follow people on Pinterest as well and so can browse through their 'pins'.
I use it to refer back to for my art related profession.
It might not be for everyone, but I like it.