@nebulon it's not the same as this, but I only recently realise that using the + sign seeming works in most places these days.
I first got introduced to it's use via Gmail and so originally though it was a feature of that, but turns out subaddressing is supported all over the place these days!
For those who don't know:
When signing-up to new services or whatever you can e.g. use username+servicename@domain.coop or username+whateveryouwant@domain.coop and seemingly in most cases (everywhere I've tried it, it works) this will still be delivered to username@domain.coop š
