Originally Posted by TheRecneps
I have bought a number of books through Barnes & Noble, and for the plugin you need to put in the activation code, which is your name & credit card number. Doing so makes me a little uneasy. Is my information safe?
It's as safe as your computer. Both calibre and the plug-ins are open source - anyone can read the code and see what it does. So it's very, very unlikely that there's any code in there secretly sending your card info to some server on the internet.
However, calibre does store the configuration info for the plug-ins in plain text, which means that your CC name and number will be stored in plain text on your computer.
You could use the stand-alone DeDRM AppleScript or windows batch file instead. I believe these only store the hashed version of your name and CC number, not the originals. There's no way back to the original CC number from the hash value.
[EDIT: I see DialDealer beat me to it. I guess I'll never remember to check whether there's another page at the end of a thread.]