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Schedule emails to go out when they're likely to make the best impression - integrates with GMail

Twitter productivity tool - allows scheduling of messages, and a variety of other tools to help you "be" in Twitter without actually being there!  Apply caution - People like true engagement! (Well durrr)

Buffer takes your tweets, and sends them at the optimal time - the time at which your followers have shown themselves most likely to see, share and clickthrough on links.