An interface to preferentially compare and choose between 2 objects, using a Tinder like interface (swipe left/right mechanics). Every year I do a stack ranking of baseball players for my fantasy league. If I had this interface, I could easily setup an ELO comparison function to create my complete list out of a series of easier comparisons.

I have at times also wished I had this for just about any sort of data tagging. Give it an array of json objects, it displays the data and then lets you swipe super quickly through all the objects in the array, semi-randomly choosing which objects to compare. Would need to write the data out as well - that's the product.

This is probably worth a couple hundred bucks to me if anyone wants to build it and open source under a commercial-reuse allowed license. Every year I spend dozens of hours doing this and don't feel like I have done a great job of making the correct comparisons.