It's been a little while since my first post covering some of the more useful drupal modules, so for all you drupal-nerds, here are a few more useful modules we use here at Best Rank to build solid, robust websites:

1. Views - A "view" is sort of like a web page or a list that spits out database driven information in a way that you specify... for example, this main blog page on our site (www.bestrank.com/blog) is a view because it displays only blog nodes (pages) and lists them by date (newest closer to the top).  We could also get more specific and create a view where we only show blog posts by certain authors, or maybe a block showing posts related to this one (as shown in the image to the right) - or get completely different and display the latest comments from pages around our site in ascending or descending order.  The possibilities are virtually limitless and the Views module is pretty amazing because it lets us build these data driven views without any programming.  For the power users, the Views module does allow for custom theming and programming to make your views very customizable.
    
2. Ubercart - need a shopping cart for drupal? Look no further, really, Ubercart is an incredibly flexible shopping cart system/module built just for drupal.  We've even got an ubercart video tutorial right here.  The only gripe I have so far is that you can't yet have your product attributes/options show up as fields in views, but that might change soon (this isn't critical just something we found out on a recent project).
    
3. Nice Menus - I am not sure why this module wouldn't be added as a core drupal module (it probably should) because it lets us create drop down menus right out of the box.  You'll have to style the css of course but the framework is built for you already.
    
4. Image and Image Cache - Another set of modules that I think should probably be in core at some point.  Image comes with several modules that let you create image galleries, import a massive number of images at once to nodes, attaching images to nodes and some other fancy image sharpening, etc. functionality.  Image Cache allows you to pre-define image derivatives, that means you can upload a large image and have, say, a small thumbnail of that uploaded image automatically be created (cropped/scaled) - kind of nice for e-commerce shops who have product images all conform to a specific set of dimensions.
    
5. Captcha - A simple module used to reduce spam submissions from your drupal forms.  The nice part about this module is it lets you display a letter, word or math test to help keep those bots away.
    
6. Secure Pages - A recent additional to our module arsenal, lets you define which URL path's should be https secured (and which shouldn't).  This is great for avoiding duplicate content issues created when spiders index the http and https version of the same page... lets say you link to your https check out page from your http cart page, and then from the https checkout page you still display your main navigation which links back to the https version of your home page and... yikes, that's a dup content issue waiting to happen.  Thankfully you can avoid those problems using this secure pages module which will print the http version of your home page link from your checkout page.
    
7. Lightbox2 - is a wonderful little module that lets you display your images in a pop-up/background-darkening format (sample image to the right).  You can have images, which are attached to nodes, display in lightbox format or even have inline images display this way! :)