OpenGoose

OpenGoose is an open-source desktop friend that runs around and brings you memes.
The memes he brings are from Gfycat, iFunny, Reddit, and YouTube, and are always fresh.

The goose can run on Windows XP, but Windows 7/8/10 is recommended (otherwise he is not transparent).
Download (or in a zip file)

Development/Modding

Unlike some existing desktop goose solutions, this goose is fully open-source and modular.
The goose itself can be extended with additional meme sources and tasks (things for it to do).

Additionally, the basic framework for creating a desktop mob has been separated from the goose itself.
This means you can create your own custom one using any .NET language (C#, VB, etc.) without having to pull apart the goose.
Source code on GitHub