This plugin can be a life saver if you ever move your site or make major updates. Came in very handy when I moved a site from one hosting account to another.
Another time it came in very handy is when I installed the Better WP Security plugin. A few of my sites were hacked so I wanted a plugin that would help make my site more secure. Better WP Security makes some major changes to your WP install if you let it. One is to change the wp-content folder name to prevent hacking bots. After doing that, though, many of my image references wouldn't work. Big problem? Not with Search and Replace. Just ran it to replace the old path with the new and I was golden. This is a great plugin!!!