Open access is a complicated business. Everytime I think I understand it (and I've blogged a lot on it, trying too get to gripes with it - in particular this post), some new nuance appears to make me realize I don't really understand at all. In this case, my mind was blown when I learnt that there was wall of shame for posting preprints on Bioarxiv! But let's back up a bit and talk a bit about preprints first.