Free Memory Gadget
Free Memory Gadget is a lightweight application with a pretty self-explanatory name - it allows you to free the memory and cache of your computer. It can be easily installed and configured, even by less experienced individuals.
The interface of the tool is based on a very small frame where you have only one button available - clicking it triggers a Command Prompter window to launch. This should clear your system's memory and cache in no time.
Unfortunately, Free Memory Gadget does not come with any configurable settings of its own. But, thanks to the default options provided by the operating system, you can move the app's frame to any spot on the screen, make it stay on top of other windows, as well as adjust its opacity level between 20% and 100%.
Free Memory Gadget has an 'Options' screen, but you can only view some app details, as well as visit the developer's website. The small tool does not put a strain on the computer's resources, as it uses a very low amount of CPU and system memory. It has a good response time and didn't freeze, crash or pop up error dialogs during our tests. Unfortunately, the gadget has not been updated for a long time.