I would donate to (and have donated to some of) the following:
- Vaultwarden
- Jellyfin
- Invidious project and yewtu.be instance
- Shynet
- Riseup VPN
- Photoview
- Jerboa
9·11 months ago- ReactOS (to transition towards x86_64)
- XFCE
- Eclipse
- GNU Image Manipulation Program (GIMP)
- Krita
- RawTherapee
- Fornjot (the CAD written in Rust)