This .gitignore is not correct. At least was not working for me.
Ignoring /media/* and then excluding !/media/customer/.htaccess is not
working. According to the Git manual, "It is not possible to re-include
a file if a parent directory of that file is excluded."
(https://git-scm.com/docs/gitignore).

Found a solution here:
http://stackoverflow.com/questions/987142/make-gitignore-ignore-everything-except-a-few-files/16318111#16318111

The other files, such as IDEs files, third-party files and system files must be added in the gitignore global of the system, not in the project scope.

with 'mage' on the gitignore file, a user can't
add files customized from Mage

The .htaccess settings depend on the development environment, in some cases it is not used.

Base is media/catalog/product/placeholder/default/ and media/catalog/product/placeholder/my-theme/ new placeholder set on admin.

without leading slash, it ignores all files with these names (cron.php,
get.php, index.php, api.php), whereveer they are

The Magento production is configured to automatically generate the sitemap.xml, as is the url is taken as a base, it is important to be ignored.

Added Configurable Swatches and Pelago lib to ignore list

According to [this](http://www.magentocommerce.com/magento-connect/thefind-feed-1.html) TheFind Feed module does not come with the latest versions of Magento( > 1.6).

Thank you

Magento keeps a log of official patches applied in this file.

The line for `install.php` blocks adding *any* file with that name. In this instance, it caused Git to ignore a file for the Aitoc_Aitsys module located at: `app/code/local/Aitoc/Aitsys/Model/Module/Install.php`