Spoiler
I rather like the pipboy 2000 one, but back when i used winamp i just had a clean generic layout. I had it minimised most of the time, and MSN messenger plus could read winamp and list my song in my status. those were the days.
I guess discord can do that with spotify now!
I'd rather like a deus ex themed OS personally. I had a system shock 2 themed windows xp back in the day and it was rather delightful, even had Xerxes voice clips for system sounds. I know its not from the linked site, i couldnt find it on there, but i knew it existed.