How can I message someone on Facebook without Facebook?
Member privacy settings can be adjusted to limit or prevent nearly any type of Facebook activity. Messaging, though, is one of the few features that are virtually untouchable by privacy restrictions. This type of communication enables members to send and receive messages with friends and non-friends alike. The only control lies in message delivery. Filtering preferences may make it a bit tricky to find non-friends’ messages. Blocking is the only guarantee that a Facebook user will not be able to read your messages.