RT's Lifecycle feature gives you complete flexibility to define your own statuses and workflow. However, if your Lifecycle has a large number of statuses, performing a simple search to see how many tickets are currently being worked on can involve building a large query to include each one. With ‘Active’ and ‘Inactive’ values for the Query Builder, it’s much simpler.
Request Tracker 4.4 introduces a number of keyboard shortcuts to improve your productivity. On any page in RT, you can now press "?" on your keyboard to bring up a list of shortcuts for the current page.
Best Practical has released a new extension to make it easy to tag tickets with useful keywords. The tags then become a link to a search for all active tickets with that tag.