GoF's desgin patterns (and Head First design patterns) are the only ones I know of.
Goal would be to improve myself as a software developer (preparing for interview design questions would be an added bonus).
Some topics that come to my mind would be:
1. Applying design patterns to real world problems. Ex. how would a you design an elevator system?
2. Architecture of some complex applications such as facebook, twitter, whatsapp etc.
3. Other common designs usually used in software engineering. For example : reliable messaging etc.
These problem and their solutions really interest me but again I don't have an exhaustive list of these topics. For example, I came across reliable messaging concept, and then I looked for it. But there may be several other topics which I haven't even heard of.