Assembla Tracker and Screen Capture
Assembla tracker is a desktop application written in Java that can quickly capture screen shots. This makes it easy to capture a screenshot and post it as a bug report. It also provides an automated time tracking feature that will log your time every 15 minutes, ask you for a task description, and attach a screenshot.
http://www.assembla.com/wiki/show/breakoutdocs/Assembla_-_Tracker_and_Screen_Capture
Tortoise SVN
Many Assembla users like to use a desktop client with SVN to make it easy to check files in and out of Subversion. There are many SVN clients available. The most popular tool in our user population is Tortoise SVN. It is a very simple tool that adds options for working with Subversion to your folder menu options. Tortoise SVN is mostly used by developers, but because it is very simple it can also be used by other members of your team, like graphic designers, marketing professionals, and business analysts.
You can download Tortoise SVN here:
http://tortoisesvn.net/downloads
IM Clients
The most commonly used outside communication tool in the Assembla community is Skype.
- Download Skype here. Basic accounts are free.
RSS Feed Reader
If you are new to RSS feeds, we recommend starting with FeedBurner, a free feed reader. You can download it here. You can add feeds every time you see this icon (try it now) 
. Many of our users prefer RSS feeds because:
Feed readers organize alerts by workspace
Assembla customizes the feed generated so that you can watch the activities of specific team members
Separating notifications from emails reduces inbox clutter