Qualcomm has pulled the plug on Eudora. However they have set a group of their developers to customize Thunderbird to make it more Eudora-like, to help current Eudora user make the transition.
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Personally, I need to use Outlook at work but I use Thunderbird at home. I also have a Gmail address and a Hotmail address (since around '95).
I have way too many email addresses, although since I have used the Hotmail for signing up for things on the 'net for years, it gets flooded with spam (that isn't caught by the Hotmail filters).