Era recommended code to Bert that included this line:
| > * ^TO_remove_mail(_at_)mysite\(_dot_)net
and Bert asked,
| An additional question: where is the backspace "\" for in the e-mail
| address? Should this be a common practice in all the addresses I use
| in my Procmail scripts?
It is to tell procmail's regexp matcher to take the period as a literal
period and not in its magic sense, where it can match any single character
except a newline. If you want to test specifically for a period, you
should escape it with a backslash.