CAD (Computer-Aided Design)
FreeCAD Portable - 3D computer-aided design (CAD) tool
LibreCAD Portable - 2D computer-aided design (CAD) tool
Diagramming
Dia Portable - full-featured diagramming tool
Draw.io Portable - diagramming tool
Pencil Project Portable - prototyping and diagramming tool
Drawing and Animation
Pencil2D Portable - 2D hand-drawn animation tool
Image Editors
AniFX Portable (Freeware) - full-featured cursor editor
Caesium Portable - image converter and optimizer
darktable Portable - virtual lighttable and darkroom
FastStone Capture Portable (Freeware) - screen capture and editor
Fotografix Portable (Freeware) - lightweight image editor
FotoSketcher Portable (Freeware) - make art from digital images
GIMP Portable - photo and image editor
Greenfish Icon Editor Pro Portable - icon, cursor, and library editor
IcoFX Portable (Freeware) - full-featured icon editor
IDPhotoStudio Portable (Freeware) - ID photo duplicator and printer
Krita Portable - sketching and painting
LazPaint Portable - photo and image editor
MyPaint Portable - digital painting and illustration
paint.net Portable (Freeware) - image and photo editor
PhotoDemon Portable - photo editor
PhotoFiltre Portable (Freeware) - image editing and effects
PhotoFilmStrip Portable - photo slide show creator
PicPick Portable (Freeware) - screen capture, editor, color picker, and more
Pixelorama Portable - pixel art editor and animation tool
PngOptimizer Portable - image converter and optimizer
RawTherapee Portable - advanced raw image processor
ScreenToGif Portable - Screen/webcam recorder and editor
ShareX Portable - Screen capture, file sharing and productivity tool
Smart Deblur Portable - sharpen out of focus and blurry images
XnConvert Portable (Freeware) - photo batch converter
Image Tools
ExifToolGUI Portable - Image metadata reader and modifier
Image Viewers
Cornice Portable - image viewer with slideshow
DiffImg Portable - image comparison tool
FastStone Image Viewer Portable (Freeware) - view, organize and convert images
IrfanView Portable (Freeware) - lightweight graphic viewer
JPEGView Portable - image viewer and processor
XnView Portable (Freeware) - view, organize and convert photos
XnView MP Portable (Freeware) - view, organize and convert photos
Rendering
AndreaMosaic Portable (Freeware) - mosaic image creator
Blender Portable - 3D modelling, animation, rendering, post-production, playback
BlenderCompat Portable - Blender with Windows 7 Support
K-3D Portable - 3D modeling and animation
Fyre Portable - 2D computational artwork
Hot Spot Studio Portable (Freeware) - mix light to create art
Vector Graphics Editors
Inkscape Portable - vector graphics editor