It’s useless for print (low res images only), but it’s not bad for websites or simply getting ideas. It also holds the prospect, somewhat akin to rummaging through a pregnant thrift store, of uncovering earthly and out-of-this world treasures. Anyone who has spent time rummaging through flickr can tell you there are many diamonds in the rough. There are many many gems in there.

The Good: Largest collection of images on the Web, Encyclodpedic range of subject matter, often very high quality, high probability of finding interesting/inspiring/useful images.