> Not so long ago a user signed up to their site using my email address (never figured out why). If they used legit billing information, with a name other than

> Not so long ago a user signed up to their site using my email address (never figured out why). If they used legit billing information, with a name other than yours, it was probably a legitimate typo of the email address while signing up, using copy-paste to avoid typing the email address a second time. They probably haven't yet realized they aren't getting emails for their account. Someone (or two people with the same name) has signed up for a Hertz car rental account and a trash removal service account using a name that could reasonably be mapped to my gmail username. I presume they either have <my_username><2/year/other_number>@gmail.com or <my_username>@<some_other_provider>.