is there such a thing as a collaborative batch transaction? 
ie multiple users who are priced out of making thier own distnct, on chain transaction, pool their utxo's together, ahead of time, and construct a single, unified, lower fee transaction, that in some way helps all participants achieve a beneficial outcome ?

i really am just thinking out loud here.. but an example use case might be to bootstrap a lightning channel(s), using almost unspend layer 1 utxos...