Hi. Is there an "easy" way to get someone's facebook profile picture using just their email address?

There is stuff online about this, but it all involves registering your "app" and jumping through hoops to get an access token, in order to get the person's facebook id. I can follow it all, and I don't think I'd have trouble doing it, but it just seems like an awful lot of effort just to be able to put people's pictures beside their posts in the comment section of a site.

I know the alternative is to use gravatars, but I think that most of my audience wouldn't have one anyway.

Also note that FBML will be unsupported very soon.