XRP Ledger is testing a zero-balance account scheme, with sponsors contributing 1 XRP as a reserve.

XRP Ledger developers are testing a SponsoredAccountCreate transaction proposal that aims to allow the creation of zero-balance accounts with a sponsor contributing 1 XRP as a reserve. This proposal aims to lower the barrier to entry for large-scale wallet creation. As of October 19th, the mechanism had received 11 votes out of 35 validators, falling short of the 29 votes required for approval. (Source: CoinDesk)