Adobe Photoshop

Price: approx. €672; also available as part of the Technical Communication Suite

http://www.adobe.com

Microsoft Expression Design

Price: approx. €729 (Expression Studio)

http://www.microsoft.com

PaintShopPro

Price: approx. €90

http://www.corel.com

Xara Xtreme

Price: approx. €299

http://www.xara.com

PhotoPlus

Price: approx. €85

http://www.serif.com

GIMP

One of the oldest, most well-known and most powerful open source graphic applications.

Price: free (Open Source)

http://www.gimp.org

Paint.NET

Less overwhelming and more intuitive than GIMP or Photoshop, but nevertheless a very professional image and photo editing software with support for layers, unlimited undo, special effects, and a wide variety of tools.

Price: free (Open Source)

www.getpaint.net

Seashore

Open Source image editor for the Mac OS X Cocoa framework.

Price: free (Open Source)

http://seashore.sourceforge.net

Microsoft Visio

Price: approx. €329 (Standard) and €699 (Professional)

http://www.microsoft.com

SmartDraw

Price: approx. $197

http://www.smartdraw.com

ConceptDraw PRO

Price: approx. €199

http://www.conceptdraw.com

Dia

Inspired by Microsoft Visio, but with a focus on more informal diagrams for personal use.

Price: free (Open Source)

http://live.gnome.org/Dia/

Creative Docs .NET

Vector-based graphic design tool.

Price: free (Open Source)

http://www.creativedocs.net

InkScape

Open Source Scalable Vector Graphics (SVG) editor.

Price: free (Open Source)

www.inkscape.org

OpenOffice Draw / OpenOffice Impress

Vector based graphics and Powerpoint-like presentation applications of the OpenOffice suite.

Price: free (Open Source)

http://www.openoffice.org

KPresenter, Kivio, Karbon1, Krita

Graphics and presentation applications of the K Desktop Environment.

Price: free (Open Source)

http://www.koffice.org

Corel DESIGNER

Price: approx. €949

http://www.corel.com

Canvas 11

Price: approx. $350

http://www.acdsee.com

IrfanView

Popular image browser and viewer. Also has some basic screen capture features.

Price: €10; free for non-commercial use

http://www.irfanview.com

Potrace (Open Source, Windows, Linux, Mac)

Command line tool that converts bitmap images to vector drawings. On the project home page you can fine also some links to free third-party GUIs for this tool.

Price: free (Open Source)

http://potrace.sourceforge.net