I have been using Gmail for quite some time now. Aside from the fact that it offers the biggest storage capability, I like their idea of having a text, voice or video chat while you are checking emails. Another thing I like is the ability to change the theme of your email account dashboard.
They have 35 existing themes to choose from. Currently, I am using Cherry Blossom. And if you don’t like the existing ones, you can always choose your own combination of colors to suit your preferences.
Here is a snapshot of available themes they have: