Amazing diagram for the first plot — deserves a PDF diagram. The way that they redefined the rankings is itself an interesting story. 
What if you used market capitalization as the thickness of the line? 
How about coloring based by market sectors (even keeping some aspects of the “when they were introduced into the list” based coloring)
The “waeving” overlapping of color stripes is problematic, or maybe just a little weird, but I guess falls out naturally from the method.
Whoa, presentation of 2 projects… good work, but careful for time….

What happened to the yellows after 94-95?

You should be able to scroll by moving your mouse to the end of the screen. Also there should be a clue that this sort of interaction is possible. (maybe an arrow or something?)

Don’t mention Apple! I totally forgot about the tablet.

It would be cool if you could filter by industry. I bet steel companies went way down in the 80s.

Very beautiful displayed, although I had trouble reading the data.  Some filter options might back the project more interesting.  -Amanda

Maybe add functionality to search for a specific company, such as a search bar. -Jon

The hovering trick is actually really clever. It might be a hack, but it’s a lot more effective than checking every curve. Props for thinking of that, I’ve had similar problems and not known a faster way to compute it than by iterating over all the objects.