David S. Goodsell has done some incredible molecular artwork depicting biological systems at a molecular level. In particular one drawing depicts a cross-section of a small portion of an Escherichia coli cell. Numerous details of the bacterial outer membrane are represented. The illustration is available at http://www.scripps.edu/pub/goodsell/illustration/public/.
The IGC Molecular Art gallery provides beautiful examples of scientific artwork online. Take a virtual tour !
(Inter)-conversion of various units can be done online at this site.