My largest contributions have been to the Wikipedia Paraty article, taking some of the statistical data from the Portuguese version of the page, and to the Portuguese Wikibook (specifically the new Brazilian Portuguese section).
I am a firm believer in Free Software (and Open Source). Hence, my commitment to using Wikipedia and Wikibooks as my primary sources of information. I run Linux at home, and have no reason to run Windows.
I have created the Language table template (suggestions for a better name are welcome). This is based on the German table template, which I think is an excellent piece of work. I made the Language table template to use in the Brazilian Portuguese section of the Portuguese Wikibook, but I hope it is general enough to be used in any language-teaching Wikibook. In fact, I hope that, in future, it can form a base for language-specific vocabulary/verb tables. See the discussion page for more on those plans.
A current problem with the Language table template is that if it is used over a number of languages, it could result in conflicting audio file names. I hope to resolve this soon.
There seem to be a great multitude of templates on Wikibooks, and it is not easy to find ones that are useful to you. There also seems to be a lot of duplicated effort, with copies made of templates for only small changes. I think that templates are a powerful aspect of Wikibooks (and other Wikimedias), and I hope they can be made easier to use. I think the duplication of effort can be minimised by using the equivalent of Object Composition to simulate inheritance. This should also result in smaller, simpler templates, which can be composed more easily into powerful templates.