Once you have installed HashTab, just right click on any file. On Mac select "File Hashes" (on 10.5 the "File Hashes" menu item will be found under the "More" submenu). "File Hashes" displays all the configured hashes for the file.
You can customize which hashes are calculated and displayed. You can hash other files for comparison. You can also paste in hash text so you don't go cross-eyed trying to compare hashes. HashTab supports the following hash functions: Adler32, CRC32, MD2, MD4, MD5, RIPEMD(128,256,320), SHA-1,256,384,512, Tiger, and Whirlpool. And if you use your iPhone, iPad or Mac OSX to manage Active Directory, be sure to check out AD Help Desk. Our help desk tool lets you perform common administrative tasks like searching and unlocking user accounts, modifying group memberships and much more.