microscopyu This is a great source of information provided by Nikon about all fields in Microscopy.
ThermoFisher Spectra Viewer This is a very useful tool to help you to check excitation and emission profiles of different fluorophores. Also great to evaluate crosstalk between fluorophores.
Science Lab This is a great source of information provided by Zeiss and Leica about all fields in Microscopy. It merges and complements the information described by the Molecular Expressions Website. Below are some links to particurarly useful Science Lab pages: