Accessories

Archive Manager
Calculator
ScreenShot(docs)
Text Editor (docs)
Zim Desktop Wiki/Notes (docs)

Education

Celestia (docs)
GeoGebra (docs)
iGNUit Flashcard Trainer
Klavaro Touch Typing Tutor (intro doc)
Phun Physics Sandbox (docs)
Scratch Visual Programming (docs, ebook, tutorials/lesson plans
curriculum guide)
Stellarium (Quick Start, docs)
Virtual Microscope (docs)
VUE Visual Understanding Environment

Games

FreeCiv
Frozen Bubble
GBrainy
Mahjongg (docs)
Mines
Multiplication Puzzle
Numpty Physics
Sudoku (docs)
Supertux
Tux Math
Tux Typing

Graphics

Agave ColorScheme Designer
Dia Diagramming (docs)
Drawpile Collaborative Drawing
F-Spot Photo Manager (docs)
GIMP Image Editor (docs, book)
Inkscape Vector Graphics (docs)
LibreOffice Draw (docs)
Pencil Animation (docs)
Scribus Desktop Publishing (docs)
Shotwell
TBO Comic Creator
TuxPaint

Internet

Empathy IM Client (docs)
Firefox (docs)
Google Chrome (docs)
Google Earth (docs)
Polly Twitter Client
Skype
Thunderbird (docs)

Office

Dictionary (docs)
Labyrinth Mind Mapping
LibreOffice Base - Database (docs)
LibreOffice Impress - Presentation (docs)
LibreOffice Calc - Spreadsheet (docs)
LibreOffice Writer - Word Processor (docs)
Nitro Tasks
Planner Project Management (docs)
View Your Mind Mind Mapping (docs)

Sound and Video

Audacity (docs)
Cheese Webcam Studio (docs)
ffDiaporama Movie Maker (docs)
Movie Player (docs)
Openshot Video Editor (docs)
Banshee Music Manager (docs)
Webcam Capture