Why DRM sucks
Some time ago I bought an eBook in PDF format. Yes, I paid for it. And it seems that the distributors thought that it would be a great idea if I couldn't open the file with any PDF reader or if I couldn't select, copy or print text from that book, so they protected it with a proprietary plug-in for Adobe Acrobat.
Now I need to read this PDF, so I thought that I would have to install that plug-in, but then I realized that the plug-in is no longer maintained (at least for Linux) and it doesn't work with current Acrobat versions so I can't read the PDF I paid.