We are using Exploratory Testing methodology for testing. We find it important to give as much information as possible about an application in as low cost as possible - be it money, time or some other resource. Exploratory testing makes this possible. Read more about Exploratory Testing from this James Bach article.
We are also using Session Based Test Management (SBTM) which is created by Jonathan and James Bach specially for Exploratory Testing.
SBTM helps to:
considerably cut down on paperwork
lower the costs for management and reports,
give a very good overview about what has been tested and why, and what are the results
You can read more about Session Based Test Management from this Jonathan Bach article.