Amazingly it appears this can be done. (But CAUTION - you can lose emails if you get this wrong!)
1) Create filtering rule that scans 'any header' for regular expression matches to a list of email addresses (probably best not to include ".co.uk" etc suffixes) separated by the | (vertical bar) symbol with no spaces before or after. (Spaces and dots may be interpreted as literals or operators depending on implementation of regular expression language).
2) make this rule first on the list of filters by making it forward email to an account with a name that starts with a letter at the start of the alphabet
3) make your email software download from this email address. Maybe change the 'reply to' address on the a/c in your email software.
This works because:
1) Filters are evaulated starting first on the list, which is always ordered alphabetically by action
2) The regular expression syntax appears to implement the Perl Compatible Regular Expression Syntax - see my more general post on email filters
3) Only one filter ever fires
Hope this helps someone!