Freeware Cleanup App. ??

Is there a decent freeware / shareware app. that will find the files left behind by previously un-installed apps?
I know I have a lot of these files on my HDD from when I first started on Mac and was unsure, so chose the "Leave files" option when un-installing

There are some that do the uninstall but not sure any will find left over bits. How would you tell the App which bits to look for if the majority of it is already gone.
You could always reinstall the ones that you know have been deleted and then use AppCleaner to remove it all.

I use AppCleaner now, but was hoping there was something that would find files that are no longer associated with the application any more, and present then for assessment and deletion at user discretion.

I seem to remember something like that for Windoze, but may not even be feasible on OS X.

How well do you remember the apps you've deleted, or the file names that were associated with them?

If you can recall details, use Cmd-F from desktop, and type in the name of the deleted application. Cmd-F (which, in fact, is Finder) will reveal what's left behind. You can use the usual Cmd-Delete to send file to the Trash.

Another option is FileBuddy SkyTag Software, makers of File Buddy which digs out all sorts of app associations - amazing!

I'll try FileBuddy, cheers.