[bb88]

Not all email validators respect the + symbol.

[cryptarch]

Most do however, and setting up your own server and making it use underscores or dashes for that purpose is one way around that.

Related tutorial on how to set that up in Postfix: https://www.stevejenkins.com/blog/2011/03/how-to-use-address...

[jrsmith1279]

With gmail you can use periods in the email address and gmail will ignore them. i.e. [e-mail] is the same as [e-mail] or even [e-mail].

[SparkyMcUnicorn]

I did that for a bit, but there's only so many variations and remembering which email belongs to which service is not nearly as straight forward.