Best practices or implementation to incorporate Facebook in websites

Last year there was a Facebook plug-in that let users invite friends by first authenticating and then picking friends by their photos. Is that still a popular option?

I was wondering if there are any popular implementations out there that let the users:

1. Post on a specific friends' wall
2. Or, send a Facebook message to specific friends

So #1 and/or #2 is done without leaving the website.

If you only want people to share it I suggest you look at the 'new' like button. It now also allows a send button next to it. Which effectively does what you want.

A link to it, with a generator. http://developers.facebook.com/docs/reference/plugins/like/

Hope that is what you wanted.