Since I am tired to constantly recite this list whenever one of these designer-type people tells me that they need Adobe’s Whatever Suite to do some basic task here is a summary that I can point them to.

Vector Graphics

Inkscape (http://inkscape.org/)
Xara Extreme (http://www.xaraxtreme.org/)

Raster Graphics

Gimp (http://www.gimp.org/)

Desktop Publishing

Scribus (http://www.scribus.net/)

Photo Editing

Gimp (see above)
Darktable (http://www.darktable.org/)
RawTherapee (http://www.rawtherapee.com/)
Luminance HDR (http://qtpfsgui.sourceforge.net/)
Layout Tools (DTP): Scribus (http://scribus.net/canvas/Scribus)