Gmail only offers filters to act upon six headers:
Want to search other headers or X-headers? Too bad. You cannot search either ‘any’ header or a specific header other than that tiny list.
Gmail also lacks wildcard searching. Say you received email from email@example.com and you searched for jim. You would not find in your gmail results jimjones’ email. If the world koolaide was in the body and you searched for the word per se you would find it but not if you searched for ‘kool’. Nor can you explicitly use wildcards: ‘kool*’. Obviously no support for regex $ (begins with) nor ^ (ends with).
Gmail does however allow you to IMAP4 fetch your POP3 email from another provider.
gmail need offer finer grain filter control. gmail is certainly better than yahoo, hotmail, and aim filtering.
The carrot feature promises better handing of in- or not-in BCC or CC, but no user control since inception.
IMAP flags? “what are those” the google team would answer. :sigh:
labs? it’d be great to have a SpamAssassin lab to take advantage of the mature SpamAssassin rules repositories.