I found that there is no any indicator of left mouse button press avaliable in XFCE4 (or any other DE). It's very helpful for disabled people when they use accessability feature to control mouse using numpad. So my frend needed such a thing in order to see if the button is pressed or not. Here is a bash implementation of the indicator.

Plank provides very minimalistic launcher for Linux. It even doesn't support hotkeys some say it's cool in order to keep it lightweight but I do love to use WIN+number hotkey to launch items from a panel as it works in Win7 or Unity. Here is an implementation of a script that will emulate this behavior for you. Certainly you would be able just to bind any hotkey to a dedicated application but the script is adaptive so it reacts on Plank items rearrangement so Win+1 for example will always launch the first item.

Not long ago I've found that Caffeine is not able to disable xfce-power-manager. A laptop screen remained on, but a system goes suspended as usual. So I've came up with an idea to replace Caffeine with my own written script. Here it is.