Helpfull tools

Zero Install
open-source cross-platform software-installation system
Zero Install allows you to run apps from NanoByte and many other sources with a single click.
NanoBlock
tricky puzzle game: stack boxes and climb over them in order to reach the level-exits
 
LightTag
a lightweight file tagging tool for Windows and Linux
M4AExtract
a small tool that extracts M4As from MP4s

Libraries for programmers

NanoByte.Common
collection of C# helper functions, used by Zero install and OmegaEngine
OmegaEngine
DirectX 9-based general-purpose 3D graphics engine for .NET Framework 2.0 and up.