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I've seen referees' reports for papers submitted to academic journals where the paper being refereed looked perfectly OK to me but the referee damned it. Different people, different judgements. Here's a bold concept: an online academic journal 'that publishes only papers that have been rejected from peer-reviewed journals (or conferences with comparable review standards) in the mathematical sciences'. Those submitting a (previously rejected) paper to Rejecta Mathematica must accompany it with an open letter; 'it is expected that the authors will discuss any known flaws in their paper with full and honest disclosure'. Is this a joke? The editors say no. (Thanks: PMc.)