Personally, I prefer
Thunderbird for mailing than the preinstalled Evolution.
If you share the same preference, surely you tried to remove Evolution from your system, just to run into a dead-end, because several packages depend on it, especially one meta package.
Evolution seems to be embedded into Ubuntu like IExplorer in Windows.
But yesterday I found some
Spanish article explaining how to remove it from the system, leaving about 56 MB of free space on your system.
I just added two more packages to the de-installation instruction that where missing for my Ubuntu 9.10 system.
Deinstall instructions
sudo aptitude purge evolution-indicator evolution evolution-documentation-en evolution-common evolution-data-server evolution-webcal evolution-plugins evolution-couchdb evolution-exchange mail-notification-evolution