Stripping out part of email content

Please see the "E-Mail Content Regular-Expression Filter" option under Setup > Email > Options.

E-Mail Content Regular-Expression Filter If provided, the part of the e-mail content that matches this regular expression will be stripped out. For example, the following expression will remove a RFC3676-style signature from the bottom of an e-mail message (i.e. a signature beginning with a separator line containing two hyphens and a space ("-- ")):    (?s)[\r\n]{1,2}-- {1,2}[\r\n]{1,2}.*$ (?s) means that the filter can apply to multiple lines at once, [\r\n]{1,2} means one or two occurrences of a newline character, .* means zero or more occurrences of any character, and $ means the end of the text. The above will filter out a signature of the following format: -- Jane Doe jane@mycompany.com (555) 555-5555

use regex, such as:   ([a-zA-Z0-9._-]+@[a-zA-Z0-9._-]+\.[a-zA-Z0-9_-]+)