BitFinder

BitFinder is a very easy to use duplicate finder that comes with a plain and simple look to appeal to all user categories.
As compared to other software solutions in this particular category, BitFinder only offers the essential options to search for duplicates, so the whole process shouldn't take more than a few seconds.
You are thus required to choose a target folder to scan for duplicates, with the task usually taking just a few seconds, but this also depends on the overall number of duplicate files and the folder size.
And speaking of file searching, the application provides two different modes, fast and normal, with the first one stressing up the CPU a little bit. The latter on the other hand is very resource friendly and doesn't affect the overall system stability at all.
Once this job comes to an end, BitFinder displays all duplicates alongside plenty of details, such as name, size, modified date and folder. You can select either one or multiple entries and move, copy or delete them in a second.
Shell integration is also available, but this particular option requires administrator privileges on Windows 7 workstations.
To sum up, BitFinder is not just a typical duplicate finder, it's more like an app aimed at rookies who aren't willing to deal with so many configuration options. It works smoothly on all Windows versions and it doesn't require any special user privileges unless you're trying to deal with system files.
It lacks several essential features for such an application, including file exclusions, advanced filtering options and more actions to be performed with the found duplicates.