• Turn off a particular smart plug
I use this in an automation that runs on my iPad. That automation is set to run when the battery charge goes above 80%.
My iPad charger is plugged into that smart plug, so this effectively gives me the 80% charge limit option that so far Apple has only added to the settings for iPhone 15 and 16, iPad Pro (M4), and iPad Air (M2). My iPad is a plain iPad.
• A series of shortcuts to control my Denon A/V receiver.
My receiver is from 2012, long before voice control was available. It does have network control (and serial port control). I've got a script on an RPi that can use the network control to change inputs, mute/unmute, and change the volume.
I've got shortcuts for mute, unmute, various volume levels, and getting the current settings for input, mute, and volume. They work by using the Shortcut action "Run script over SSH" to invoke the script on the RPi.
I've got an Amazon Echo Dot next to the Denon, with the line out of the Dot connection to one of the Denon analog inputs. When line out is connected to a Dot the internal speaker is disabled, which makes that Dot useless for things like checking the weather or timers unless the corresponding Denon input is selected, so I've got the mic on the Dot disabled and use an Echo Show in the same room for all those things. The Dot's job is strictly to supply input to the Denon.
So let's say I want to listen to some music. I can say "<Apple>, Denon Dot" to switch the input to the Dot. (I'm writing "<Apple>" instead of Apple's phrase to trigger their voice assistant so if anyone ever happens to run this through text to speech it will be less annoying. Similar for Amazon's voice assistant).
Then I can say "<Amazon>, on Dot listen to Classical KING FM on Dot" and the echo Show will start the Dot streaming KING FM to the Denon. (It is only actually necessary to say "on Dot" once, but which of the two is necessary occasionally changes, and it is easier to just say it twice).
• Open the "OTP Auth" app.
That's the app I use for TOTP codes on my iPhone. It supports Apple Watch, but asking Apple's voice assistant on the watch to "open OTP Auth" isn't reliable (maybe...[1]). My first choice alternative to voice would be a widget in the Smart Stack but OTP Auth does not have one.
Shortcuts can be put in the Smart Stack. Hence, a Shortcut on the watch that simply launches OTP Auth.
[1] I say maybe because that is based on my old Series 4 watch. I recently upgraded to a Series 10. That has on-device Siri, and I've noticed that is way better. It did not occur to me to check of "open OTP Auth" is reliable.