Dear gene90,
I didn't believe it either, but is seems that red blood cells have been isolated from a T rex. Althoug the cells weren't viable, the authors were even able to invoke an immunological respons to proteins from the red blood cells. A scientific discussion on this topic can be found in: Earth, June 1997, p55-57 (Schweitzer, M. and Staedter, I., The real Jurassic Park). It is 'weird' stuff.
best wishes,
Peter