Storing information that the user shouldn't be able to access?

Question

Hello all,
I'm not sure if this is the appropriate place to post this but feel free to move this post to a better spot if its in the wrong place. Hope you guys can help me I have a program that requires the user to register such as entering a cd-key and other information that proves that the software was purchased. At this point that information is stored in a file where the program later reads from that file to determine wether or not it is indeed unlocked and available for the user to use. Using this method I found that the user could simply copy the entire folder where the program is located including the file that tells the program that it is registered, to another computer. This allows the user to simply copy it to endless computers without ever registering it again. I can see this being posted online somewhere and there goes my program off to everybody for free :(
What i'm asking is do you guys have any suggestions on how I can make sure the files containing registration information don't get read or copied by the user? So far here are my theories:
1. Make a file with a name that doesn't seem associated with my program and put that file in a location that isn't easily found.
*2.* Require the user to activate the software online. Keep track of how many times the specific cd-key has been registered online and limit it to three installations. This would be my preferable method because if a cd-key was given out to say 10 people it wouldn't matter because that cd-key can only be registered 3 times online. However I have no idea how to let a java program write data to an online source yet I know how to read from an online source. (As a side question if anyone could point me to some tutorial where I could learn about writing data to online sources that would be great) If you've ever used Adobe Photoshop CS3 it would hopefully be kind of like their registration method. I don't know if that is possible with Java, though so far it seems anything is possible with Java :)
Any suggestions would be great. Thanks :)

Answer 1

I just realized I am not playing fair, if I am going to ask you what yours does i should have said what mine did.
So, my software that netted me $25,000 basically was an inventory helper for factories that do fabrication. Basically I was in school and working construction as a forman (was my grandpas company and I had grown up around it) full time. I realized that most of the workers under me were very talented at building things, but sucked at basic logical things like going to the scrap pile and finding the board just barely longer than the one you need to cut instead of just grabbing a new board and generating more scrap that means more waste and less profit. After trying to pound this concept into the guys over and over "Your christmass bonuses depend on how little waste we have guys, c'mon" (but with lots more swearing, cause it was construction after all), I realized that this was probably a problem lots of fabrication buisnesses struggled with. So I wrote a program that used a touch screen and a printer that printed on sticker labels (both commercial off the shelf items). When inventory was delivered someone printed up stickers for all the inventory that had a unique tracking number and it's current dimensions written on it. Didn't matter if it was steel, fabric, wood, plastic, or whatever. When someone needed something they went to the touch screen and navigated to the category (type) of material they wanted and then entered the dimensions they needed. The program automatically figured out which exact peice they should grab to use and if they should expect the scrap to be entered back in as a usable length. If it did expect scrap it kept track until the person came back with the new dimensions of the scrap and a new sticker was printed. If scrap was expected but not generated eventually management was notified. Management also got to see who was using what peices, and exactly what kind of inventory they had on hand.
I got a lot more than $25,000 from the three companies, but I also had to buy computer, touch screens, label printers, pay taxes, get buisness license, pay fees, maintain a second phoneline for "buisness calls", and all sorts of other things that ended up making my pay actually banked for work done about $25,000.
I sold it to three different companies in the area I lived along with a 3 year contract to fix it whenever broken and the option for them to get new features added at minimul cost. That was 15 years ago now. Of three three one company paid me a little more after the three years ended to get the code ( they wanted to extend the maintenence and service contract but I was moving). One went out of buisness before the three years ended, and the third couldn't convince their employees to use it and ended up giving up on it.
My game that got me $200 was just a simple side scroller, back when those where popular. I used the $200 to buy an RC car, and released two "updates" with some of the better feature ideas people sent me with their donation (was mail, long before paypal).
JSG