A way for an Agile team to collaboratively schedule its EngineeringTasks.
I first encountered the string-and-paper wall-gantt in Manzo's 2002 http://www.stsc.hill.af.mil/crossTalk/2002/10/manzo.html (in CrossTalk? magazine, of all things!). There are photos of it on slides 47-48 of http://sunset.usc.edu/events/2003/March_2003/Agile_Methods_Perspective_ARR_John_Manzo.pdf
A Google search also turns up http://hyperthink.net/blog/default,date,2003-11-29.aspx, though I didn't find pictures there.
See also: AgileGantt