I don't use the Terminal in OS X much, but when I do I prefer something a little more refined than green text on a black background. Without further ado, I present my current custom theme Slate.

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I am using the wonderful, and free, Input font from Front Bureau.

Color Palette

Background: 45 45 45 with a 90% opacity and 100% blur, opacity dropped to 80% when inactive.
Text: 255 255 255
Cursor: 199 40 111