Is there a mechanism by which you can put aside a lump sum of money (before or after your passing) wherein the money can just sit and earn interest in a safe investment in perpetuity and disbursements to charities of your choosing can be made (also in perpetuity) at regular interval? We're talking a relatively small sum of money - say $100k for example.
I guess it's probably too good to be true.
If it doesn't exist, which of the above mechanisms would come closest with the least hassle and fewest fees?