Protocol Online Collects and organizes many of the protocols that are available on the Web into a coherent database.
Cell Biology Laboratory Manual Basic cell biology methods,including cell fractionation, electrophoresis, microscopy, cell culture and differentiation experiments. (Gustavus Adolphus College)
 DNA Sequencing Lab Protocols Protocols for DNA purification and sequencing  (Whitehead Institute/MIT Center for Genome Research)
Herskowitz Lab Protocols Methods for S. cerevisiae genetics, cell biology and biochemistry (UCSF) 
Microscopy Methods Light  and transmission electron microcopy, including protocols for cryosectioning, immunocytochemistry and other preparation techniques  (House Ear Institute, Los Angeles)
Molecular Biology Protocols Protocols for DNA purification, transformation and sequencing, PCR, electrophoresis and homology searches  (NWFSC)
PCRlink.com.   PCR techniques