I just had to login to a windows server using VNC, and I was required to "Press CTRL + ALT + DELETE to log on". Not as easy as it sounds on a Mac laptop which has no "Alt" or "Delete" key. And a quick Google pointed to remapping keys on the keyboard which did not appeal to me.
After a bit of playing around I found the equivalent keystrokes that will work:
"control" + "option" + "fn" + "delete"
No keyboard remapping required.
Hopefully that saves you some time if you ever have the need.