A reminder to Nautilus readers that Nature Protocols Volume 2 is open access to the end of this month. So far, there more more than 250 protocols in the volume — please visit Nature Protocols and check them out for yourself.

Whether you want help with an experimental technique, or can offer advice on the questions already posted, please join in the debate on the free Nature Protocols discussion forum on Nature Network. There are currently 26 topics in the forum, with many questions and answers, on subjects including insoluble proteins, mitochondrial DNA from plants, immunoglobulin and other protein purification, large cloning fragments and hydrogen peroxide detection.