No interest in developing this myself, so any culinary entrepreneurs out there who fancy having a go, be my guest (and send me a nice cake as a reward). I think there is some real potential for a paste that allows cooks to glue together parts of cakes that have fallen apart. It is quite common for cakes to break during kitchen processing, so a simple paste that allows people to stick them back together, without of course changing the taste, could be an essential item in every home cook's baking cupboard.
It could be a neutral-tasting paste that the cook spreads on both halves and then just puts them back together. Or it could use the remaining cake mix as a base, with an added agent to cause it to 'self cook' over an hour or so using the remaining heat in the cake.
Being able to salvage not just the cake, but also the reputation of the cook, would make this a valuable tool.