I just got back from the 2008 Webvisions here in Portland. There were a number of interesting presentations and conferences are always good to get revitalized. One presentation that was of particular interest to me was by Sean Larkin of OpenSourcery, where he covered Drupal as a development platform.
Here's a quick summary of their top Drupal modules (please forgive me if I've made any errors):
- CCK (Content Construction Kit) - allows you to add different field types
- Views - allows custom queries
- Contemplates - allows editing of presentation
- Theme API Module - allows editing the header and footer w/o a Node
- ImageCache - upload high quality images and create lower resolution versions; also allows adding borders, backgrounds, etc.
- TincyMCE - best WYSIWYG editor
- IMCE - a file manager that works with TinyMCE
- Gmap - module for Google Maps mashup
- PathAuto - module allows you preserve older URLs
- CustomError - custom 403 & 404 errors without needing to create nodes for them
- Ecommerce or Ubercart - robust ecommerce modules
- Devel Module - helpful for developers; grab arrays and see what's in them
For theming the you can find custom themes in the Theme Garden or start from the Zen theme