Apple doesn’t make it easy to change certain parts of your Mac’s user interface, but arm yourself with the right tools and you can make radical changes with the help of third-party tools. And when it comes to customising or tweaking your dock, you can’t do much better than Scottish donationware tool Docker.

The app simplifies the task of changing the physical appearance of the dock, plus provides all the tweaking options you need for your dock, including those not provided in OS X itself – all under one roof.

Once downloaded, launch Docker to find yourself at the core part of the app – its Styles & Colors section. Here’s where you can change its appearance by replacing the Dock’s background plus indicator and separator graphics. Rather than go to the trouble of designing your own, visit LeopardDocks.com to find dozens of replacement docks to choose from.

Change your dock's appearance with just a few clicks (and downloaded files).

Download and extract the contents to a single folder on your hard drive, then choose Custom Images from the appropriate dropdown menu and click Select Folder to point Docker towards the new designs. Once down, click Apply and follow the prompts to produce your radically revamped dock.

It doesn’t end there – you can also tweak various dock settings, like those found elsewhere in Finder, plus some additional tweaks like quickly and easily generating new Stacks and Spacers. It all adds up to an indispensable part of your OS X custom toolkit.

Docker 1.6.7 is a free download for Macs running OS X 10.5 (Leopard) through to 10.7 (Lion).