Having read an excellent work recently - mentioning no names just yet - the provision of a review seems like it would inform the public ever so slightly, and (more importantly) give feedback to the author.
Sadly, it isn't clear precisely where the review page/submodule/form is located, and opinions are rapidly approaching critical mass. A signpost or directions or message in a bottle explaining where the UI is currently hiding the "write review here" feature would be a boon of great value.
When you're logged in to the main site, if you scroll to the bottom of the listing's page there's a text box where you can add your review.
Aaaand Darwin award has absolutely no competition. Thank you, you lovely potato.