In the U.S. one can attach a copyright symbol to their work and make it effectively "copyrighted", but that does not happen here automatically. There are also some rules which come into play when people post materials on "public" forums, such as this one, particularily if they have notices which state that materials posted on the Forum become the property of the Board.
Leaving that all aside, I belive a "crackme" author might be considered in the U.S. to have given "implied consent" for "fair use" of the material for its "intended purpose," which in this case would be to figure out how to "crack it." I also believe that the DMCA requires the copyright holder send "notification" of the alleged violation of their copyrighted materials to the operator of the web site and then the website generally can avoid problems by "removing the materials." The website can also send notice to their ISP that they dispute the claim of copyright infringment, agree to accept legal service from the claimant, and then the claimant has 10 days to commence formal litigation in a local Federal Court, or the claim may be invalidated.
This is what happened originally on the Woodmann site, a "reported" claim of coryrighted materials which Woodmann disputed and notified the ISP of his willingness to accept service of process. In otherwords, he "called the bluff" of the ISP and they immediately changed their tune and said there was no DMCA claim but they would be booting us off anyway for "violating their policies, revealed through their unexplained "internal investigation." There really isn't a hell of a lot one can do is the ISP really wants to terminate your contract. So now the server has been moved again, and this time to a country which is not bound by the DMCA.
But, again, they could always boot us again, for almost any private reason they wanted to use also. But maybe, this time, the desire for "money" with prevail.
Regards,