I use a variant of this, I sign up with myusername+uniqueid@mydomain.org, where uniqueid is something I will later recognise, often a shortened version of the t

I use a variant of this, I sign up with myusername+uniqueid@mydomain.org, where uniqueid is something I will later recognise, often a shortened version of the target domain name. This has the advantage of being easy to filter and see where from a particular message originated from, and at the same time, it does contain my username, which makes it easier to search for me.