Boomerang for Gmail
Schedule an email to be sent later. Easy email reminders. Boomerang for Gmail is a Firefox / Chrome plugin that lets you take control of when you send and receive email messages.
Podcast about how to use Boomerang: Trick People into Thinking You are a Good Person & other Lifehacks
A Must Have for Life Hackers
Email is constant battle front for life hackers and productivity rock stars. Make sure to listen to the Limitless Mindset Podcast #21 where I describe how I use Boomerang.