It would be useful for GreenHopper to freeze the column headings when you scroll down - this would help to maintain context when navigating large boards. Another advantage would be that the quick filters would remain accessible even if you've scrolled a long way down on a board - this would enable you to navigate the board much more quickly. For example, when you're using a Kanban board and you've closed many issues already, you can have a long list of closed issues. If you've scrolled down to look at an issue and now want to move to another part of the board, you currently have to scroll all the way back to the top to change a filter or look at other issues. With the suggested change, you could click on a "Hide Closed" quick filter and go immediately to the top.
It would also be useful if the Swim Lane name could be frozen until you scroll to the next swimlane.