If you're looking for something that can go beyond a one-to-one remote desktop experience and actually control multiple computers, PC Monitor (free, Windows Store) is worth downloading.
As with TeamViewer, it's free to non-commercial users and it promises to keep an update of up to three computers. PC Monitor can see if the PCs are logged into, view and kill processes, run scheduled tasks, and get granular detail on PC information about memory usage, operating temperature and the CPU.
You can also check and install Windows updates, and monitor the list of installed applications--handy if you want to keep employees on task.
LogMeIn's JoinMe may lack the power and finesse of some of the above applications but it's a more than just useful for remotely viewing other screens and online meetings.
The Modern-style app (free, Windows Store) supports ARM (for Windows RT devices) and x86-based Windows 8 PCs, including tablets and mobile phones. It's simple to set up. All you need to do is download the app. After that, you'll be able to receive invitations to screen-share from colleagues or friends.
A Pro version costs $19 a month or $149 per year. This adds the capability to customize notes when sending out meeting invites, to view your meeting history, and to schedule follow-up meetings.
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