Use Epics to group product themes or feature sets (You can order these independently from the Backlog)
Break epics down into sub-epics or stories into tasks
Hovering over a collapsed epic will expand it.
Assign categories to projects to group them on the project list.
Use comments against the Project to record key project information or decisions.
Use comments against an Iteration to keep a log of your standups and retrospectives
Select a card, hold the left button down and use 'page-up/down' or the up/down keys to move cards large distances.