Josh Nankivel, the PM Student, posted a video about a month ago that I finally got around to viewing. It is How Kanban Helps Prevent Multitasking on Project Teams, and he describes exactly that.
I really like the focus on using something (Kanban) to help visualize the work that is happening in a group. It's a means for facilitating a conversation around priorities when something new arises - such as everyone's favorite "drive by" work. There is also a key element buried in his discussion of the Kanban board: the organization has to be bought into the idea that priorities will be set and managed by the local teams - whether they are project teams or not.
Josh provides a little more context at Gantthead, where he posted the video, How Can You Prevent Multitasking on Your Project Teams?