Default. All the other skins have one color or text color combination that looks bad to me - that light cream/yellow on dark blue in the night vision for example. My eyes just do not like that combination.
You don't have mine listed. I used the "Name me - June Contest" It was a contest from years ago and then I think, TCS had some technical problems and it never got named. It dissapeared for a while, after the big crash a few years back. But then suddenly appeared again and I LOVE IT!!