Today I discovered one very fantastic compression utility, called 7z. That's a compression technology similar to Zip or StuffIt, but the compression ratio is fantastic.
Not that it is a brand sparking new compressor, but it's rather me being slow again ;)
So as a test, I tried to compress something with it just to try how good is the software. The place of "something" took Mac OS X's standard Mail.app (I guess it's because it sits on the top of my Dock..). To compare compression ratio with more widely used compression technlogies, I compressed the same file with OS X's Zip archive, as well as .tar archive bzip2'ed at highest compression level (bzip2 -9).
The results are on the picture below:

Compression times are the following:
- Zip: about 5secs
- bzip2: about 11 secs
- 7z : about 18 secs
7z shows to be the slowest, but there are times when you'd better wait for a file to compress better :)
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