Rainmeter  4.5

Customize your desktop with various skins, displaying the weather forecast, battery power, available memory, notes, to-do lists, etc.

Rainmeter is a free, open-source desktop customization toolkit that lets you add 'skins' to your Windows desktop. The hallmark of the software is its customization ability. It uses an easy-to-learn coding language that allows you to create and modify your skins, making it a robust toolkit for tech-savvy creatives. Although you'll need to put some time into learning the language, the flexibility and personalization that comes with this are more than worth it.

Each skin can be seen as a separate window, and you can run multiple skins at the same time, even from different sources. They range from simple gadgets like on your Android device to complex live displays for anything from computer performance to music visualizers. You can move them around freely on your desktop, experimenting with the aesthetics of your digital workspace.

Every skin is made from measures, gathering information from various sources, and meters, creating visual elements. The unique code language of Rainmeter even enables skins to interact with other skins or applications. But the true beauty lies in Rainmeter's open source nature. Each skin's code is open for tweaking and modification, allowing you to create a truly unique user interface.

Without a doubt, Rainmeter's strength lies in its supportive and creative community of users. Over the years, they have churned out an impressive array of beautiful skins and are always on hand to help each other out.

However, users should bear in mind that Rainmeter won't replace or change any native Windows components – it doesn't modify the appearance of your taskbar, start button, or desktop icons. It's also not a window manager, meaning it won't handle your open windows or control multi-monitor setups.