This is a simple HOWTO to obtain support for Google Gadget plasmoids for Kubuntu 9.04 Jaunty.

Install google gadgets library packages:
  sudo apt-get install libggadget-qt-1.0-dev
  sudo apt-get install libggadget-1.0-dev

Install kdebase source and dependencies:
  apt-get source kdebase-workspace
  sudo apt-get build-dep kdebase-workspace

configure the kdebase project:
  cd kdebase-workspace-4.2.1a
  cmake .
  
compile the google gadgets script engine:
  cd plasma/scriptengines/google_gadgets
  make

Copy the binaries:

../../../lib/plasma_package_ggl.so -> /usr/lib/kde4/plasma_package_ggl.so
../../../lib/plasma_scriptengine_ggl.so -> /usr/lib/kde4/plasma_scriptengine_ggl.so
plasma-packagestructure-googlegadgets.desktop -> /usr/share/kde4/services/plasma-packagestructure-googlegadgets.desktop
plasma-scriptengine-googlegadgets.desktop -> /usr/share/kde4/services/plasma-scriptengine-googlegadgets.desktop
plasma-applet-ggl-photos.desktop -> /usr/share/kde4/services/plasma-applet-ggl-photos.desktop
config.txt.photos -> /usr/share/apps/plasma/plasmoids/ggl_photos/config.txt
plasma-applet-ggl-rss.desktop -> /usr/share/kde4/services/plasma-applet-ggl-rss.desktop
config.txt.rss -> /usr/share/apps/plasma/plasmoids/ggl_rss/config.txt

Copyright notice: this guide was written by Francesco Santini (rincewind _at_ tin.it), 28/03/2009, and is released under a CreativeCommons-Attribution-3.0 license.