[ Thanks to Frank Cox for this link.
]
“Sylpheed works very well with gmail. You can download
your messages to your computer and read them offline if you wish.
When you have multiple email accounts on various mailservers (as I
do) then you can use Sylpheed to aggregate all of your email in one
place. Sylpheed can sort your email using various filters, and it
has native support for spam filtering using bogofilter or
bsfilter.”