myDVDEdit. Works like ResEdit (an old res fork editor for Mac. Never really used it, but often software cracks would call for changing something with it. But that was in the old days, when apples had floppy drives, and SCSI ports) - or so it claims. But the page is a lot more useful (or useless) for it's detailed information on DVDs.
I found a tape of Into The Woods - Original Broadway Cast, I believe! Shall be watching it sometime this week, and maybe, if it's good enough, see if there's spiffy ways to convert it to DVD/digitize it with our new camcorder.
K, I'm going to bed now... I keep typoing. :P