Got multiple Windows Live accounts? Sick and tired of having to log out and back in again to switch between them? Well, no more! You can now link your Windows Live IDs together so you can switch identities in one click from the menu on the top right of most Windows Live pages. To set this up, go to https://account.live.com and look for the section called Linked Windows Live IDs. There's a link there to manage your linked IDs and if you click that, you'll get a screen where you can add IDs.
Once you have this done, Sign Out, and then Sign In Again. When you go to sites like Windows Live Spaces and Windows Live Events, you can click on the top-right of the Windows Live header bar (click on the down arrow next to your name) and you'll be able to instantly switch to any of your linked IDs.
A few quick security notes: