One university professor writes that he suspects as many as 25–30% of the graduating seniors at his university were guilty of some form of cheating. I'm a bit put off by his emphasis on Wikipedia as a source of cheating—though I don't doubt that it's often the source of plagiarized material, that's just because of its prominence as a source of information. The tone just strikes me as typical “blame Wikipedia!” style hysteria. The comments are also excellent in an entirely different fashion: somehow the cheating problem is the professor's fault, because they are either failing to engage the students, assigning too much work, or the assignments fail to require student creativity, facilitating plagiarism. Also, fantasy-land is an excellent place which you should visit! The only serious complaint is that many students get in trouble because no one has done a good job explaining citations to them, meaning that they are merely dense instead of scum.
In any case, he raises the point that sites such as Student of Fortune, which offer answers to questions on an as needed basis, and provide all original content thereby make it much harder for professors to catch cheaters.* I'm tempted by the idea of a legal mandate to give universities access to these sorts of sites, so that the written content would be searchable just like what's on wikipedia. Obviously, there is both a demarcation problem in terms of identifying the sites which would be subject to the law, and a matter of the political impossibility of passing such legislation, but I suspect this is a decent idea in principle.
(*)(I think it's irrelevant that one has to question Student of Fortune's impact, given that its top earner has made $43.50 so far. There are other sites that offer original content and do greater business.)