UPDATE: This post is quite old now and wont work with the latest version of WYSIWYG API, will try to update this soon.
Gallery2 is one of the best galleries available which could be integrated with Drupal easily you would have read my post on integrating it earlier, after you have integrated it the bigger question is how get those images into your content or nodes so this posts answers it, after reading this post you would be able to integrate Gallery2 with your WYSIWYG (TinyMCE) Editor.
Typing and display of any language other then English is always tough on the Internet to ease this we had various plugins coming in, i had also written a blog for akindic plugin for Drupal 5 last year, but what about the later and better versions of drupal, Gamabhana provides indic typing support but does not works with WYSIWYG API so this blog presents you a solution to type in Indic on Drupal using WYSIWYG API with TinyMCE
Drupal uses the php mail() function to send emails by default.
Here is a module which adds SMTP functionality to Drupal. More specifically, the ability for your site to send mail using an SMTP server that requires authentication.
Link to Module http://drupal.org/project/smtp
This module is currently in Beta stage for Drupal 6.x, i just tried it works fine and you can use this too. remember to read INSTALL.txt before installing this module as there are certain dependencies which are needed to have this module working.
This module uses the smtp and mail class’s from PHPMailer. http://phpmailer.sourceforge.net
Guest book is one of the essential part for any website, To add a guestbook on your drupal site you can use the guestbook module, the problem you would face is adding a captcha to this now captcha is also very essential to control spam now how to add captcha its very simple just execute the following query
INSERT INTO `captcha_points` ( `form_id` , `module` , `type` )
( 'guestbook_form_entry_form', NULL , NULL );
and you are done now go to /admin/user/captcha on your site and enable captcha on guestbook this would look something like this