Since build 1607 of Windows 10, it automatically restarts after updates, regardless of your wishes or unsaved documents. And since I do most of my work on a Virtual Machine that runs 24/7, this is not desired behaviour (putting it mildly).
In previous builds, there were options to postpone restarts until you manually approved. Not anymore...

This article by Martin Brinkmann shows a way to fix this: http://www.ghacks.net/2016/09/20/disable-reboot-after-automatic-windows-updates/
I did not install the "Take Ownership" program; doing that manually is easy enough.

Note: This solution worked fine for a while - however, recently (June 14th 2017) Windows somehow undid the fix (all settings were set back to their old status) and restarted my VM anyway. Bugger. I've implemented the fix again, hopefully Windows will keep its dirty hands off this time...

It happened again, while multiple applications were running (Feb 14th 2018)... So I had another go at it; this time I tried the suggestions mentioned here: https://docs.microsoft.com/en-us/windows/deployment/update/waas-restart. Fingers crossed.

Adobe Photoshop and Lightroom claim a lot of disk space on your C drive for caching purposes. I wanted to move those files to another SSD (E in my case), so they wouldn't be included in the daily C disk image backups. Of course this applies to other applications as well, this is just an example.

For Camera Raw cache files this is easy, just change the location in Photoshop or Lightroom itself.

For the Lightroom Catalog Previews, this is a bit more complicated. There is no setting for that one, so we'll have to use a symbolic link. A great article on those can be found at https://www.howtogeek.com/howto/16226/complete-guide-to-symbolic-links-symlinks-on-windows-or-linux/.
I moved the Lightroom Catalog Previews.lrdata directory from C:\ to E:\Adobe\ and created a symbolic link like this:

mklink /J "C:\Lightroom Catalog Previews.lrdata" "E:\Adobe\Lightroom Catalog Previews.lrdata"

I have some scaling problems with VMware ESXi 5.5 vSphere Client (and VMware Workstaton Player 15.5) on Windows 10, escpecially since buying a 4K monitor. This problem is not limited to VMware of course, any old piece of software may have similar problems, so the fix here might be of use.

Windows 10 is now 5 years old, and still multi-monitor scaling has issues. Sigh.
I would really like Microsoft to concentrate on fixing bugs instead of adding new features (99% of which I never use anyway).
And this is by no means the only old bug in Windows they refuse to repair - just last week Windows Explorer failed to remove a folder from it's Navigation Pane after removing that folder in its main window. I have been running into that stupid little bug since at least Windows 2000...