Sure — here’s one. Despite the prominent display of a search bar at the top of the page and prompting that occurs with each new question, Quora is still plagued by users asking questions that have already been answered multiple times (e.g., “I am a computer science student. Can you recommend ideas for a graduation project?”).
For your project, consider this problem from a UI/UX perspective: how should the site have been set up differently to allow you to have seen previous answers? Should you have needed to acknowledge the previous answers prior to being permitted to ask a question? Should questions that appear to be too similar to existing ones require moderation before going live? Should users be penalized if too many of their questions end up being merged?
Consider that most of the problem lies in the lack of specificity of these kinds of questions. Asking for a graduation project in compiler theory is probably unique, and if it isn’t, the question is rare enough so that duplication isn’t bothersome. Would part of your solution allow responders to mark the question with “Not enough information”, causing the question to be suppressed until the requested information is provided?