The following is Edsko de Vries' freemind overview of The Catsters' Category Theory videos. A linearized (text only) version is available as well if you prefer (for instance, if you are on an iPhone!).
The diagram is meant to be read left-to-right, top-to-bottom, with stuff coming “later” (more to the right/lower on the page) requiring an understanding of the material before it (there are some exceptions, but hopefully only “conservative” ones). To use the diagram, open up the section you are interested in and click on the arrows to open up the corresponding YouTube video.
Suggestions for improvements are always welcome.