Spherical nanoparticles are attracting increasing interest for diverse commercial uses due to their many useful attributes such as applicability as controlled-release systems and their super-hydrophobicity. In this review, methods of particle formation for cellulose, its derivatives, and related species are discussed with reference to numerous specific examples. Techniques for characterization of particle size, size-distribution, and related properties under both dispersed and solid particle conditions are summarized and contrasted. Finally, we note potential applications for these surprisingly reproducible nanospheres.