I wish I had an easy way to find threads from two years ago, I frequently remember one I’d like to reread, but can’t find.
A way that has been touted recently (which I've been doing for a while is to use the advanced google.com search parameter that limits results to a single domain.
For example, enter: "SJackson" site:freerepublic.com
in the google search text box and you'll see your own posts. (Or one's with your username referenced.)