yes. Its actually built in to the OS. To make a file into a zip file, just right click the file or ctrl+click the file and a menu should come out. Select create archive. And you should see the zip file in the same folder as the original file. HTH
Mac OS X has built in zip utilities or expander. To zip file, right click file or folder> "Create Archive". To unzip, double click the file or right click - Open. There's a third party called Dropzip developed by Aladdin Systems. HTH.
sitting on my desktop is an 83mb pdf file that i wanted to email to a friend... since file is obviously too big, i tried to compress it by doing the following actions: *right-clicked on file *chose the option to "create archive of" so and so it created a zip file still on my desktop.. but file size was the same, 83mb.. what gives?
as jopoy suggested, try yousendit for sending large files. PDF files are very compact files so zipping them doesn't necessarily gain you any compressed space. You'd see big compression ratios for TXT or Word files.