Recently, one of the DVDs that Eli and Gus like to watch became corrupted. I'm not sure exactly what the problem is; there aren't any obvious scratches, and we've cleaned it. The symptom is that during one of the scenes, the video freezes.
So, I ripped the data off of the disc using ddrescue, managing to get all but about 800K of the data. I can play the resulting ISO image using the awesome VLC. There's a brief pause in the video where the missing data occurs, but otherwise it plays perfectly.
So why am I a criminal? The DVD data is scrambled with CSS, which of course requires libdvdcss to unscramble. And since CSS is legally a mechanism to guard against unauthorized copying, unscrambling the content is illegal under the DMCA.