Eudora Replacement

[bob at rsi.com (Bob Gorman)]

At 10:58 AM 10/12/2004, miah wrote:
>Nice HTML only email.  Don't forget that most of us are actually linux
>users / developers and probably don't use Eudora or a HTML capable
>email reader.

Sorry about the oversight and thanks for the reminder.

As I gently push myself away from a MS-Windows based desktop to one built on Linux, I find that an email client is one of the big pieces of functionality that needs to be replicated.

So I'm looking for recommendations for a client-based MUA that approximates the functionality of Eudora.  In preparation for this I have moved my mail archives to an IMAP server.  I have also been working up an itemization of functionality that is important to me.  Here it is so far if anyone is interested:

  Ability to interact with multiple accounts, imap and pop.
  Ability to leave mail on server.
  Ability to automatically store copy of mail on client for off-line perusal.
  Ability to drag-n-drop mail from inbox to other mail boxes/folders.
  Ability to automatically synchronize client and server mail boxes/folders. 
  Ability to have many complex mail filters.
  Ability to not have a preview pane.
  Ability to handle creation of simple html mail.
  Ability to handle display of complex html mail (from MS-Windows clients).
  Ability to easily add attachment.
  Ability to easily launch viewer for attachment.
  Ability to easily save attachment to a file.
  Ability to handle simple address lists.
  Ability to remember and display recently used addresses.
  Client must be separate discreet application, not part of a web-browser, PIM, etc.
  Desire to have a highly customized user interface to match my personal style.

I expect that there default GNOME and KDE mail clients do most of this. However, any feedback or pointers is very much appreciated.  URLs, FAQs, RTFMs also acceptable.  TIA.