Will_D:
Did you try re-slicing the part? Did you try printing a different part? And if you did - did it make any difference? If it didn't make any difference, then look at your machine for problems. Otherwise look at the slicing software.
Like I said in my post on the 23rd, this would periodically happen to me when I was using Slic3r, or the Prusa version of Slic3r. The first time it happened I was also wondering WTF happened to this piece of crap now? When I couldn't find anything wrong with my printer, I tried re-slicing the part - printed with no problems. After that, when a part started screwing up the first thing I did was re-slice the part. If that didn't fix the problem, THEN I started looking at the printer.
I don't remember now which axis was shifted on my machine, and that's not just a "Senior Moment" type of thing, I haven't used Slic3r for close to 2 years. Don't get me wrong, Slic3r and Cura are both good slicing packages. But until something better comes along though, I'm going to stick with using Simplify3D.
Don