Methods

Journal of visualized experiments

Contains extensive video material illustrating different methods: http://www.jove.com

Laser scanning microscopy

Contains the presentation: A walk into microscopy covering basic aspects of different microscopy types: http://www.charite.de/laserscanningmicroscopy/

Electrophysiology

Free textbooks into basic electrophysiology:

The axon guide:
Very good introduction and classic into the basics and underlying physical principles: http://www.moleculardevices.com/pages/instruments/axon_guide.html

The Plymouth workshop on microelectrode techniques:
An older but detailed and informative textbook on electrophysiological techniques: http://www.utdallas.edu/~tres/microelectrode/me.html

General information for electrophysiologists: http://www.ionchannels.org/

Microscopy

http://micro.magnet.fsu.edu/

JCB journal watch - might be trivial for some, but usefull for others:
Jennifer C. Waters. Accuracy and precision in quantitative fluorescence microscopy. J Cell Biol. 2009;185 1135-1148. doi: 10.1083/jcb.200903097.

Methodological Protocols

A wide variety of methodological protocls can be obtained here: http://cshprotocols.cshlp.org/

Molecular Imaging

http://campus.acr.org/acr/mils.aspx