I've been working on a wordpress plugin that is unlike any other that is out right now. In fact, there are none even in the same ballpark as this. Not only that, but it is extremely useful. I've been using it on my wordpress sites for awhile, but it was extremely elementary and lacked features. So I started rewriting it a couple weeks ago, and I'm almost done with it. I am now about to release it, and am looking for ways I can protect myself. I am looking to sell licenses for $25 a pop, because I think it's a very fair price for it. So if anyone has been in a similar position, how can I protect myself from somebody just buying a copy and then redistributing it. I mean obviously there's obfuscation and a callback to a server of mine, but I want people to be able to use this on any wordpress site not just the one they register with. Not only that, but if the callback server goes down, or I switch hosting or something, everyone's shit out of luck! So I'm looking for other methods perhaps. If I was doing freelance PHP work I would have made at least $500 with the time investment, so I really don't want to be a victim of theft. I'm thinking on top of obfuscated code, maybe I'll have a panel for customers to add URLs of their sites with. Then there will be a callback, and self-modifying code. There's 3 scenarios: 1) It pings my server and gets a 404, the plugin will still work, but it will still want to ping everytime it's used until it gets confirmation. 2) If it pings the server and the URL is in my database, it will modify the code to not have to callback anymore... and will store an encrypted version of the URL within the self-modified code somewhere. It will then check that instead of pinging the server! If the decrypted version of the URL doesn't match the URL the plugin is on, the plugin will ping me and then also delete the plugin's folder and its contents. 3) And the 3rd scenario, it pings my server and the URL isn't in the database, is similar to the self-destruct in scenario 2. Is there another better way perhaps? But not only that, I've never sold anything online before (Well, that is if you don't count affiliate programs!). I think paypal would be the best option, but how can I protect myself both in selling the product (I'm guessing no expressed or implied warranties?). Not only that, but how do I prove delivery of such a digital product in case someone tries to be an asswhole and charge back after I've given them the plugin? Thanks!