I just stumbled on this one (Yes, this is only new to me):
A.T. Robertson's Harmony of the Gospels allows you to pick the translation! I don't know how long this has been in there, but I like it.
I wanted to set up a reading plan for the Gospels, but I wanted to read in historical order, not book by book. However, I assumed I would have to use a fixed translation. Imagine my surprise when I could build a reading plan for a harmony AND I could pick the translation.
And, of course, the parallel resources lets me switch between harmonies - this is all getting a little excessive. 
