P.S. GitLab is now the official location of the tint2 project, migrated from Google Code, which is shutting down. In case you are wondering why not GitHub, BitBucket etc., we chose GitLab because it is open source, it is mature and works well, looks cool and has a very nice team.
What is tint2?
tint2 is a simple panel/taskbar made for modern X window managers. It was specifically made for Openbox but it should also work with other window managers (GNOME, KDE, XFCE etc.). It is based on ttm https://code.google.com/p/ttm/.
Panel with taskbar, system tray, clock and launcher icons;
Easy to customize: color/transparency on fonts, icons, borders and backgrounds;
Pager like capability: move tasks between workspaces (virtual desktops), switch between workspaces;
Multi-monitor capability: create one panel per monitor, showing only the tasks from the current monitor;
Customizable mouse events.
Be unintrusive and light (in terms of memory, CPU and aesthetic);
Follow the freedesktop.org specifications;
Make certain workflows, such as multi-desktop and multi-monitor, easy to use.