SMF is a powerful file search and duplicate finding tool that uses hashing (MD5, CRC32 or SHA1) to determine similarity. Includes a host of filter capabilities and a result-reporting tool, with which you can sub-filter the result set according to your needs.
The program lets you search by last modified date, keyword, or file attribute; pictures of a certain filesize, dimension, or metadata info; MP3s by length, author, or bitrate; and duplicate pictures that have a certain filesize or dimension.