Customizing the Mail Filter

The email filter on mail.sas uses the configuration the file .procmailrc in your home directory. You can edit it yourself with a text editor such as pico or emacs. Look for the lines: 
# whitelist example; remove #'s to use
# :0:
# * ^From: .*user@address.edu.*
# $ORGMAIL

# blacklist example; remove #'s to use
# :0:
# * ^From: .*user@address.edu.*
# caught-spam
EXAMPLES

Below "." is a "wild card" that matches any character while "*" will repeat the match, so ".*ams" will match any string of characters that contains "ams". To match a period, use "\." A line beginning with "#" is a comment that is ignored by the filter. $ORGMAIL means your usual incomming mailbox.
By default these matches are not case sensitive and search the mail header only. The last example below searches both header and body. 

# Saves messages with "AMS" (not case sensitive) in the subject
:0:
* ^Subject:.*AMS
$ORGMAIL

# Saves messages from New York Times Direct
:0:
* ^From:.*nytdirect@nytimes\.com
$ORGMAIL

# Saves messages from the list server "ems-epc"
:0:
* ^To.*ems-epc@
$ORGMAIL

# Catches any message with "buyit.cn" in the body or header
:0 BH
* buyit\.cn
caught-spam
For more information, see the man pages for "procmailex" and "procmailrc". A Google search on "procmail" yields lots more. [Creating exotic filter recipies is tricky. Not recommended for novices.]