The Molecular Expressions website features photo galleries that explore the fascinating world of optical microscopy. Molecular Expressions offers one of the Web's largest collections of color photographs taken through an optical microscope (commonly referred to as "photo-micro-graphs").
Howard Berg at the Rowland Institute, Harvard, maintains a collection of on-line videos of many kinds of motile bacteria, including E. coli, Salmonella, Rhodobacter, Pseudomonas, Mycoplasma, and more. Includes flagellar, twitching, gliding, and Mycoplasma motility.
The RCSB Protein Database provides a variety of tools and resources for studying the structures of biological macromolecules and their relationships to sequence, function, and disease.