Here is the list of top 50 drupal modules by average monthly downloads. This data is as of 2009. With Drupal's popularity increasing the download data may vary. But the top downloaded modules are not likely to change much.
Drupal does not have any special web hosting requirements. You can host a drupal site with any PHP / MySQL web hosting provider. However there are some web hosts which provide some excellent support and features for Drupal sites. Most drupal hosting companies will provide you with Auto Installation or Free drupal installation.
You will stumble across several drupal hosting providers , here are few things you can check for.
Some Top Drupal website sorted by Category. The sites are not in any particular order. If you want your site to be listed here Contact Us. For guaranteed inclusion you can give a site recipe or some tips on how you made your site. Basically some code/article which will be value add for Drupal developers. Your article will be featured on the website along with your site in showcase.
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