I recently went away with a group of friends and would love to share the photos. I've tried Flickr, but it seems quite restrictive in many ways. Is there a site which allows me to join and then share them by emailing people some sort of password in order to allow only them to see it? (two of my friends are well-known celebrities so I can't risk putting them on a public site) Also, I'd like the people who have the password to then be able to comment on and even upload their own photos to that same set. Is this possible? Thanks.