2bits.com has been contributing to Drupal for many years.
We have contributed features to Drupal core, such as patches to the contact module, the site offline feature (since 4.7), and the logging framework (since 6.x).
In addition, we have contributed tens of Drupal modules to the community. Most of these were commissioned by clients, and then released to the community. They can be further extended and customized to your specific needs.
You can find a list of contributed modules that we occasionally update to be in sync with Drupal.org.