Nice, Zmatrix, it reminds me of the Doctor Who intro sequence lol. Although, you made the mistake of using textures rather than procedural materials, and thus you have pixelation (on the vein wall) and mapping artifacts (on the cells). Anyway, here's my new one:

...did anyone else notice that it gets blurred like a DoF effect in the back?? I never put that in...(/shifty eyes)