Skippy-XD is a lightweight full-screen window picker for X11, similar to the Mac OS X "Exposé" feature, useful for desktop environments like as Xfce or LXDE, which don't have such a feature by default.
There are Compiz and KWin plugins that offer similar functionality (and GNOME Shell has this built in) however, Skippy-XD should work with pretty much any NETWM or GNOME WM Specs compliant window-manager: Xfwm4, OpenBox, FluxBox, WindowMaker, IceWM and so on.
Skippy-XD is triggered by a hotkey and it displays thumbnails for windows on the current desktop, allowing you to easily pick a window by using the mouse or keyboard. You can also close windows by middle clicking them.
The application supports live previews, videos included, and uses compositing, but only when you press the hotkey to display the window picker.
The Skippy-XD development stagnated for a while but now it has a new maintainer and appears to be active again. Recently, the application received support for closing windows (middle click), customizable tooltip position, VI movement keys (h,j,k,l) and many bug fixes. Right now, Skippy-XD doesn't display window decorations but according to a bug report, that should change soon.
Below you can watch an old video with Skippy-XD in action:
(direct video link)
Note that the video shows adding the Skippy-XD daemon on startup but from what I've read, the daemon is pretty buggy so you should simply use "skippy-xd" to launch it - or the script I've posted below, under "Usage", which works around an issue with Skippy-XD not showing minimized windows.
Install Skippy-XD in Ubuntu
Ubuntu users can install the latest Skippy-XD from GIT by using a PPA. Add the PPA and install Skippy-XD using the following commands:
sudo add-apt-repository ppa:landronimirc/skippy-xd-daily sudo apt-get update sudo apt-get install skippy-xd
You'll also need to create a configuration file called "skippy-xd.rc" under ~/.config/skippy-xd/. You can install the default Skippy-XD configuration file by using the commands below:
mkdir -p ~/.config/skippy-xd wget https://raw.github.com/richardgv/skippy-xd/master/skippy-xd.rc-default -O ~/.config/skippy-xd/skippy-xd.rc
This file has various Skippy-XD options which you can change: the window update frequency, colors, opacity, mouse bindings and so on.
Arch Linux users can install the latest Skippy-XD from GIT via AUR.
For other Linux distributions, you can grab the Skippy-XD source code from GitHub.
Report any bugs you may find @ GitHub.
Skippy-XD has a bug and doesn't display minimized windows. A work-around for this is to use a script created by B. Murphy. Download and install the script using the following command:
sudo apt-get install xdotool wget https://raw.github.com/hotice/webupd8/master/skippy-xd-fix -O /tmp/skippy-xd-fix sudo install /tmp/skippy-xd-fix /usr/local/bin/
Now let's assign "/usr/local/bin/skippy-xd-fix" a keyboard shortcut from the system settings. If you're using Xfce, you can assign a keyboard shortcut to the Skippy window picker via Settings > Keyboard, on the Application Shortcuts tab, click "Add" and under command, use "skippy-xd-fix".
See how to set up keyboard bindings for Openbox | Fluxbox.
If you want to use the Skippy-XD daemon instead, see THIS wiki page.
To set up a hot corner for Skippy-XD under Xfce, LXDE, etc., you can use an application called Brightside.