I always just remapped it to the super button, and most applications actually automatically map it to the super button.

I use my context menu key as the chording key to control any keyboard macro profiles, so that I can terminate, reload, summon for editing or summon a help file as needed.

I have lots of shortcuts bound to it except I never press it because I have the caps lock key mapped to the same keycode and that's easier to press

It is a component of the keyboard shortcuts I use to swap between virtual desktops and snap windows to the left/right side.

Meta+T opens a terminal about once every 5 minutes on my machine.

System shortcut with combination of other keys to mainly switch between virtual desktops, open terminal, open MangoHUD config file and some more

Left: start/stop playing music via xmms2

Right: open a zenity file selector to load music into xmms2

Compose key

Mostly the same as Windows, ie for opening the application launcher menu, as well as for a variety of global shortcuts.

for xmonad commands. also windows-p is dmenu.

• Meta by itself just opens the launcher thingy in KDE so I can search for an app.
• Meta + T = Open terminal
• Meta + E = Open Dolphin (this is a Windows holdover, Meta + E opened Explorer but it's kind of hard-coded into my brain now)
• Meta + F = Open Firefox

I think that's all of them.