PubPeer seeks to create an online community that uses the publication of scientific results as an opening for fruitful discussion among scientists. With PubPeer, scientists can comment on almost any scientific article published with a DOI or preprint in the arXiv.
PREP (Platform for Responsible Editorial Policies) is an online platform contributing to the responsible organisation of editorial procedures of scholarly journals.
Review of a neat new tool that provides a cool function for many academics: GPeerReview is a very simple Open Source tool that lets you write a review of a work, embed a hash of the work in your review, and sign that review with your digital signature (using your GPG key).