In the NLP direction I can highlight:

- the project of a fully autonomous (without internet access) virtual consultant based on open source LLM answering on a given knowledge base (RAG) (summer 2023, when everything was just starting);
- project of virtual examiner with LLM for automatic compilation of questions and semantic evaluation of users' answers on the given material.

Also in this direction were projects of document processing, virtual assistants with integration, etc. In fact, it is not so easy to single out the most interesting ones, because it was interesting to work on all of them)