Found a link on another forum to this interesting PDF:
http://www.aiaa.org/pdf/industry/ShuttleVariationsFinalAIAA.pdf
The document itself (which I believe is from 2004) is interesting enough, showing some of the shuttle derivatives that never happened. I'm familiar with many of them, but this one at the bottom of page 6 caught my eye:
Look familiar?
http://www.aiaa.org/pdf/industry/ShuttleVariationsFinalAIAA.pdf
The document itself (which I believe is from 2004) is interesting enough, showing some of the shuttle derivatives that never happened. I'm familiar with many of them, but this one at the bottom of page 6 caught my eye:

Look familiar?
