[merlyn]

Most of my training classes lately has used VitalSource. Apparently they take their DRM pretty seriously, and hide their keys pretty well, and rotate them often.

There's some older DRM strippers for it that no longer work, I'm guessing anybody that has a working set of key extraction won't tip their hat on it.

Of course lo-tech methods can work well enough.

And FWIW: Kindle seems to be switching over to ePub as the default method.