Whenever a Bag of Holding is put inside another, they both implode, losing themselves and everything inside them into the void forever. Other similar accidents have resulted in countless other sort of stuff, sometimes up to and including entire ships or Spelljammers or even a kingdom or two, to have been similarly cast drifting outside the material planes, which has over the millennia swollen into quite a pile of treasure. Due to hidden magical winds within the nothingness, all this debris, flotsam and jetsam, eventually ends up in the same place. A hidden pile of treasure, the biggest in the multiverse, ripe for picking for anyone that can get there first.

Getting in is easy: just get yourself two Bags of Holding, and climb inside one while having the other one with you. Now getting out, or surviving for that matter, is a different thing altogether.

Would this make for a viable adventure?