I wonder if it is possible in Stellar to forward the transaction costs onto some other (willing) account (and still maintain its private seed). I could go into the rationale, but its really not relevant.
In other words:
if Account A wants to send XLMs to account B, can it somehow use account C to pay for the transaction fee, assuming C is willing? In addition, of course, no account shares its private seed with another account in the process.