For those of you who use Outlook as your email client, here are a few useful shortcuts:
Ctrl-Shift-O: Switch to out-box.
Ctrl-Enter: Send current message.
Ctrl-R: Reply to a message.
Ctrl-Shift-R: Reply All to a message.
Ctrl-Shift-A: Create a new appointment.
Ctrl-Shift-M: Create a new message.
Ctrl-1: Switch to Mail.
Ctrl-2: Switch to Calendar.
Ctrl-3: Switch to Contacts.
Ctrl-4: Switch to Tasks.