One thing I can't help missing from Windows is the amount of decompression tools available.

There are far fewer on Mac, although Pacifist makes up for that as an application that can handle a huge range of compressed packages including .pkg, .dmg, .zip, .tar, .tar.gz, .tar.bz2, .pax, and .xar archives. Most importantly, it gives you full control over which files you want to unzip, which is useful if you need to install just one file out of a package instead of the entire package. The most common usage of Pacifist is to roll-back unsuccessful or problematic updates, especially to QuickTime.

Simply open the package you're having problems with in Pacifist and click on the Verify button. Pacifist then checks to see whether all files are installed correctly and have the right permissions.

Alternatively, Pacifist could be handy if an installer isn't functioning correctly and you need to extract only those files that are essential. It can even open certain archives via HTTP, which is handy in case you want to download only one file from a large .zip archive without downloading the whole file. As a final bonus, Pacifist can also find which installer installed which programs. This is ideal if you've got a program installed that you have no idea how it got there.

There's very little to criticize in Pacifist. It's a superbly versatile and powerful archive tool that may one day be standard in OS X.