My desk setup is typical enough. A 2 year old Macbook Pro, a 22" external monitor, a 1TB hard drive. But I found that despite the 130 odd applications I use, only a few of those are used regularly. Some of those are open constantly and that's what I'd like to share.

Plex ~  Plex is a media player/media library/a lot more. The most recent versions included plugins to incorporate youtube, hulu, CNN and much more. This lives on my external monitor. To check the latest news on CNN I merely open that feed and browse the list of the news vids. It's clean, quick and free. On the media side it has some of the best HD support available for a mac player - in particular that love it or hate it MKV container.

Mailplane ~ Not free but useful. Essentially mail plane is a shell that allows you to run the gmail web interface as a separate application. This may sound like just another browser window but not having to flip windows to access my mail and the growl integration makes it worth it.

Adium ~ A well know client for aggregating various chat clients into one list for easy use. 

Celtx ~ One of the best screenplay editors out there. Best of all... free.