I'm a fan of a good User Interface, and I have a nickname for bad ones that make you move, click, and scroll way too much to get simple tasks done - Carpal Tunnel Systems. The first system I had called this was a CMS (Content Management System) so the acronym made sense more in that context... Anyhow.

When you manage your inbox, many times you know what to do with an email before you even open it. Is it Spam from the Hormel corporation, a offer from a Nigerian prince, or an ex-girlfriend that won't stop stalking you? Maybe you are busy when an important email pops up and you want to flag it for later. Outlook.com enables you to set up one-click actions that perform these actions instantly. 
To configure quick actions:

• click the settings icon in the toolbar
• select 'More email settings' from the menu.
• select 'Instant actions' under 'Customising Outlook'
• make sure 'Show instant actions' is   checked.

You can also add your own instant action buttons by clicking 'Add actions' and selecting other options from the menu, such as 'Move to' / 'Categorize'. To make the button always visible, highlight the button under 'Show on mouse over' and move it down until the button is set to  'Show always'.

Outlook.com's sweep feature allows you to clean up your inbox and keep it that way automatically.

Wait... what? yeah.

This doesn't just blindly delete all your stuff. One example of it's use would be if you get automatic emails with special offers that are only valid for a short period of time, you can have Outlook.com automatically clear out old versions of the email when the latest one arrives.
 
You can set up automatic cleanup for a sender's mail or a category in Outlook.com, open a message from the sender or newsletter you would like cleaned up automatically, click 'Sweep' in the Outlook.com toolbar and then select 'Schedule cleanup' from the menu.

You can choose:

• 'Only keep the latest message from this sender',
•  'Delete all messages older than __ days' 
• 'Move all messages older than __ days to <select>'.

Optionally, you can select 'Do this for everything in the ___ category' and apply your rule to all emails classified as Newsletters or whatever else you choose.

Next click 'OK'.

That's it, now sit back and enjoy your new automatic self cleaning inbox. Thank you Outlook.com