A perfect calendar with Gregorian, Jalali and Hijri support; with english and persian translation of interface; For GNU/Linux with every desktop environment(Gnome, KDE, Xfce, ...). It is writen in PyGTK and uses system tray like an applet.
Nice! More steep than Rainlendar and very (!) customizable interface (but look by default will probably frighten some :)
Nice work ! Great project.