Jonny T Designs is my personal portfolio. - http://www.jonnytdesigns.com
I use JonnyTDesigns.com not only for showcasing my work. It also works as a CRM on the back end and the greatest part its all run off of Drupal. No other open source solutions needed because Drupal does it all.
Modules used:
Admin Menu
Admin menu is a great module that allows for quick administration of a website when the administrator is logged in. I use it for all my sites I can't live without it.
CCK
I use CCK to create different content types allowing easy management of content.
Chart+Google Analytic's API
I use to chart and Google Analytics API to track statistics of my site without having to leave my site.
Storm (For Client Management)
I use storm to track time spent on my clients projects.
Also I use storm for invoicing.
Ctools+Panels
For landing page creation so easy its almost wrong. =]
Jcarousel+Views+ViewsCarousel
To create seamless carousels that are easy to mod.
Views
Creating views of my portfolio work and services I offer, along with user management.
Webform
Webform makes creating webform's an extremely easy process, and it stores all of the data input so it can be used at a later time or to create a report.