Any recommendations for a new tutorial?

Hi there,

A couple years into learning to write software. This place was where I began asking all the noob questions and as I grasped more.

I'd like to give back more, and seeing as tutorial section seems low on content that seems like a good star. Here are some ideas I was thinking of to write a tutorial for similar to length and simplicity to above, mainly patterns seem like a good a choice.

Observable pattern [with events or with interfaces not sure yet]
Decorator pattern
Wrapper pattern
Visitor pattern

Chain of responsibility pattern.

https://stackoverflow.com/questions

Suggestions on which is best is nice thanks.