Hiri for Windows

Fast, good looking email client. Lighter than MS Outlook with some unique and clever features.

Basics:
- Fully integrated calendar
- Tasks
- Contacts
- Built for Exchange, Office 365 and Outlook.com
- Uses Microsoft's own protocol - EWS. So if you need to go back to Outlook, everything will be synced.

Nice features:
- Great task list built in. You can just drag an email to the right-hand side to make a to-do item out of it.
- Super fast search
- Triage emails using the Action/FYI filters.

- Deal with emails using the 4 D's - Defer, Delete, Delegate and Do.
- Send emails with actions
- Dashboard and timer to remind you not to check email too often (this is a really bad habit!)
- Nice touch - the subject line is at the bottom of the compose window. You'll write a better subject line AFTER you've written your email. Get your emails noticed.