I would think these type of cards would be more prominent in basketball, I also think it would be cool to own one. I have a card with a piece of a basketball on it, but that's about it. I don't collect too much basketball cards though, but imagine a series of NCAA cards with nets from each school that won their conference or post season tournaments. It has a lot of potential, or even a insert set of school with the most championships. I think that would be a big seller, especially now with so many people inflating the prices.
I never thought about hockey having similar cards, but again, I don't collect too many hockey cards either. Do they make hockey cards with pieces of pucks on them, that would be cool. I assume they make some with pieces of the sticks.
Royal Card Review is my blog if you feel like checking it out, thanks if you do!- royalcardreview.blogspot.com/
In the process of updating my collection so don't trust any of my lists right now.