The just-released Mailplane 2.1.6 from Uncomplex adds built-in support for the highly interesting Rapportive plug-in (see "Rapportive Plug-in Replaces Gmail Ads with Sender Info," 27 March 2010). Mailplane 2.1.6 also now works with the Share > Send via Mail menu items in the iWork '09 applications. With them, you can email your document via Mailplane in its native format or as a Word, Excel, PowerPoint, or PDF document. A few minor bugs have also been fixed, some of which were related to Gmail changes. ($24.95 new, free update, 6.7 MB)
Quick Download of Multiple Attachments in Apple Mail
To download a bunch of attachments quickly, look in the header of the email message that they came in. Make sure the triangle adjacent to the paperclip icon is pointing to the right (click the triangle if needed), and then drag the paperclip icon to your Desktop or to another folder. Release the mouse button and all attachments copy to that location.