Antetype is a design and layout software focused on visual design. It saves you a lot of time creating and optimizing UIs.

InterfaceLIFT is an app for wallpapers.

Wicd (Wireless Interface Connection Daemon) is an open source software utility to manage both wireless and wired networks for Linux.

PowerPro lets you take control of how you use Windows.

Grsync is a graphical user interface for rsync.

MockFlow is a collection of wireframe tools, prototyping tools, UI mockups, UX suite.

Microsoft Blend for Visual Studio (Microsoft Expression Blend) is a user interface design tool.