The right tool for the right job? Like scrum make it agnostic fluid and save me time, time, time.

Normally I don't gush over products but I love anything that reduces the time it takes me to do anything - so below are the best in their special areas.

Pivotal Tracker is brilliant. We used it with internationally distributed teams. Your ability to do sprints, be agile needs to be quite slim - however; trust the product to manage your cycles for you, don't sweat the old school fat that you may have previously known. The Pivotal guys are really quite clever, they have great experience and understanding in the scrum, xp arenas. So working with a Ruby/Rails TDD team that is truly self organising means you don't need the below large suite.

For shared services departments with multi-channel product distribution we're using the atlassian suite - seamless and continuous communication from confluence to jira to greenhopper to fisheye/crucible to bamboo (with SOAPUI integration) to dare i say it - HPQC - for the old school testers, and back again to do it all over again.

The differences are obvious in the pricing models. I do frown a bit at Atlassians training prices for their products.