There’s currently no way of earmarking donations for a single OTW project or expense. There are several expenses that are non-project-specific and related to the organisation as a whole: for instance, the software that our volunteers use to host meetings and make plans; the server hosting that works for both our internal documentation and AO3 content; and the firewall that protects Fanlore, the Archive and our internal storage. Donations go towards the upkeep of all these and other OTW projects.