DNA is a fascinating molecule that serves as an information storage medium - the blueprint for life. Nature manipulates and copies the information stored in DNA through the action of a large family of enzymes, each of which function as a sophisticated "nanomachine". We used one of these machines, DNA polymerase, in conjunction with single molecule spectroscopy in order to determine the sequence information stored in single DNA molecules. Such experiments may form the basis of powerful new, massively parallel, genome sequencing technology, as well as providing a new assay to study the properties of DNA polymerases. We have also used a variety of other physical techniques, including optical tweezers and near field microscopy, to directly image information stored in DNA at both molecular and macromolecular length scales.

One important manner in which microfluidics differs from microelectronics is that the fundamental physics changes more rapidly as the size scale is decreased. Despite decades of ever smaller transistors and higher densities in semiconductor electronics, the industry has yet to reach the length scale where scaling has caused a qualitative change in physical phenomena, e.g., from theclassical to the quantum regime. Single electron transistors and other mesoscopic devices have been developed, yet remain exotic objects of laboratory exploration. By contrast, fluidic systems can rather quickly reach length scales where the fundamental fluid physics changes dramatically. I will review the nature of some of these effects and how they can be exploited.