The Letters section of Physics World has always reflected the interests, passions and obsessions of physicists around the world: nuclear power (usually pro but sometimes strongly con); educational standards (falling); the image of physics (bad); women in physics (must encourage more); science and religion (polarized); and scientific units (endless fascination). We always enjoy hearing from you and encourage you to write and e-mail in. From this month, we are renaming our Letters section as Feedback and including selected, edited comments to stories appearing on our website physicsworld.com. These comments, which are often fired off by readers as soon as a story is posted, may lack the formal, measured tone of a typical letter to the editor, but they benefit from immediacy, variety and, sometimes, directness. We hope you enjoy them — and that they encourage you to visit physicsworld.com and add thoughts of your own.