I've used Flickr with success too. Shutterfly also offers unlimited photo storage as well and you can create your own share pages. For example, on vacation I took a lot of photos of my friend's children I wanted to share with her. I uploaded them, created a password protected share page and gave her access to it. She was able to save them to her own Shuttefly photos and download them without compression compromising photo quality, yet the photos were protected from random folks browsing through them.