GAHHHH. So jealous. I was hoping I'd be the first to make a widget for the HML!!!
This great, Brian. I'll play with it a bit and see what suggestions I can make. Here's one that might not be too hard: on the Try It page let the user be able to set the number of cards to something besides 8. This would let you try weird edge cases (like what happens when there's 1 card?), or scale a solution up to run on many more cards. You'll have to experiment to figure out what you max is in terms of screen real estate but I could imagine scaling up to a point where the visualization just looks like a list of numbers, rather than showing the actual card faces (you know, like hint, hint, nudge nudge, it's not about the cards).
Cool. Cool. Cool.