Q. Can you use bitcoins for matanot laevyonim on Purim?

A. Bitcoin is a cryptocurrency and worldwide payment system. It is the first decentralized digital currency, as the system works without a central bank or single administrator. (Wikipedia).
Horav Shlomo Miller’s Shlit’a opinion is that if the transfer to the needy is done effectively on Purim and if he can then pay for food with it, or cash the transfer and acquire food with it, one complies with the mitzva of maatonos loevyonim. (See question 1024 in regards to the amount to be given).

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit’a