I don't know about that but soon we 'll see bitcoins mentioned in prenups
if you need to write a prenup then you have failed already.
not just the fact that the 'other half' may leave you someday to think a prenup is needed, but also that you dont have a separate bank account/ paperwallet to put YOUR hard work into.
most successful marriages are where both people only put in a percentage of each of their personal earnings into a single pot. then if divorsed its easy to manage who owns what and what needs to be split by checking which account paid for it.
EG my new car paid with my bank account = mine after divorse.
the house paid for using the joint account meaning the house gets split.
if you manage your funds right from the start there are no need for special contracts, only trust. and if you cant trust someone.. dont marry them