I am a 13 year programmer, and had stumbled across this website: http://bitcoinmaniac.com . This inspired me to update my site to look more modern: http://nahtnam.com The creator of bitcoinmaniac contacted me VIA PM on http://bitcointalk.org (which is down due to DDOS attack), and told me to give him credit. I refused, and he started spamming my threads on that forums, and looked up my address from the WHOIS of my site, and started posting it on http://coinchat.org I gave him credit to keep him quiet, but I really do not want to give him credit. Do I legally have to give him credit? I have not copied any of his source code, only the layout. Thanks a lot for all of the help you can give!