I create a new, unique e-mail address -- alias, technically -- for 99% of all sites where I register/sign up that require one. To be more specific, I have my p

I create a new, unique e-mail address -- alias, technically -- for 99% of all sites where I register/sign up that require one. To be more specific, I have my primary "me@example.com" e-mail account that I use. When I register/sign up at www.company.com, I create an alias of the form "zzz-company@example.com" which goes to "me@example.com". I do this primarily for exactly the two reasons you mentioned above. FWIW, I run my own mail server and all e-mail accounts and aliases are stored in SQL. A small script that I wrote makes creating a new alias entry in the database quick and easy, e.g.: $ newalias zzz-hn Also, that's a literal "zzz-" prefix. I do this to avoid any "coincidences" where a spammer tries to send mail to a random address that actually exists as one of my aliases. That is, a spammer may try to send to "hn@example.com" which very well could exist. A spammer would be much less likely (it seems, anyways) to try to send to "zzz-hn@". I was on vacation out-of-state last week and we ordered a pizza from Papa John's one evening. I didn't have my laptop handy (only my iPad and iPhone) so instead I used the "checkout as a guest" option and employed the "+" separator trick (i.e., I used "me+papajohns@" as my e-mail address). I try to avoid this whenever possible and create an actual alias as some sites a) don't allow "+" as a valid character or b) are aware of this "trick" and simply strip off the suffix, thus ending up with my real e-mail address. (For the curious, the confirmation e-mail was sent via ExactTarget and they didn't strip off "+papajohns".) I just started doing this several months ago but it helped me discover that either the dealership I bought my newest car from or Reynolds and Reynolds (who provide an application the dealership uses) shared my e-mail address with Edmunds.com, who later started spamming me. Because I do this, however, that situation was easy to take care of (delete alias and blacklist the sending mail servers).