Please note: Educational web sites are listed under "Learning & Teaching"
The confocal microscopy list is the place for all questions related to confocal microscopy. It works as an e-mail distribution list to which anybody can subscribe. The online archive goes back to 1991 and is thus in itself a valuable resource.
Kurt's Microscopy Blog is a blog by Kurt Thorn at the UCSF. Among other things it regularly features 'paper roundups'.
Microscopy and Analysis is another free paper magazin.
Associations & Conferences
Funny enough, although much of modern microscopy was developped and is built in Germany, there is no professional society for light microscopy or bioimaging yet. There is now, however, an open association of German microscopists, German BioImaging. The website features a list of core facilities. Several work groups deal with topics such as training, image analysis, microscope standardization.
EuroBioimaging is an initiative to create a European-wide biomedical imaging infrastructure.
The European Light Microscopy Initiative ELMI was, as it states on the website, "created in 2001 to establish a unique communication network between European scientists working in the field of light microscopy and the manufacturers of their equipment." ELMI may be best known for their yearly conferences.
Not an association but also famous for their yearly conferences is Focus on Microscopy.
The German microscopy forum has a long list with lots and lots of web sites on microscopy, most of them in German.