I thought I had requested this before but I don't see it anywhere. Currently the getTransaction and getTransactions API calls will yield transactions that are donations, and even provide Donation IDs for them.
However, it's not possible to pull any info about a specific donation, given a Donation ID, through the API. Would love read if not read/write access to donations and donors over the API, with the ability to filter like we get in the Donations module.
As it is right now I pull the data out of a backup zip and work Excel or SQL magic on it but it's tedious.