I have a few pages which allow users to upload entries into the database for apartment postings etc. I have seen a few similar sites which have been over run by people posting huge lists of links to porn pages etc. I would like to allow users to post without making them create a user id and password which they would have to use to sign in every time. There are two questions here. First: why do people want to post web links like this and Second: Is there a way to prevent this without creating a user id password feature for all users? Thanks.