Alt+Tab, Task Switcher, tap and release to alternate between current and last window. This usage pattern comes up a lot.

Ctrl+Alt+Tab, open task switcher and leave it open

Win+Tab, open task view

Ctrl+Win+<left/right arrow>, move between virtual desktops

Ctrl+Shift+v, paste as plain text

Win+v, show clipboard history

PicPick, screenshot/screen capture tool.

ScreenToGif, capture screencasts as animated Gifs