PerfectClock is a customizable software that displays multiple world-time clocks with fast and flexible options. The skinnable program offers unlimited functions to personalize your experience.
With PerfectClock, you can add an unlimited number of World-Time clocks to your desktop, making it more convenient to keep track of the time across different time zones.
On the other hand, Screenlets is a widget engine and a set of independently-developed widget applications. It is designed to run primarily on X11-based compositing window managers, with its most notable architecture being the Compiz (under Linux).
Most importantly, Screenlets offers support for both Python and SVG scripting, giving developers more options when creating widget applications. The software has also added support for web widgets, allowing developers to write widgets in HTML, JavaScript, and CSS, which is similar to widgets for Apple Inc.'s Dashboard.
Overall, the Screenlets widget engine is a solid choice for anyone looking to create and customize widgets on their desktop. The diverse range of scripting options, combined with its compatibility with most compositing window managers, make it a must-have for widget enthusiasts.