I don't think that there's a way to do it here at MacRumors, but if you've participated in the thread you can use Google to find it. Just go to Google and type in a word or two that you know were in the thread, your user name and "site:forums.macrumors.com" (without the quotes). You can then use "Search Tools" drop down in the sidebar of Google to narrow it down to a specific time frame if there's too many results initially.