There's been some fun research done on the topic of progress bars and user perceptible wait times. (To the surprise of absolutely no-one who is paying attentio

There's been some fun research done on the topic of progress bars and user perceptible wait times. (To the surprise of absolutely no-one who is paying attention, a) people suck at math and b) if one has accurate knowledge that a process will take 100 units of time, coloring in 1% of the bar per unit of time is provably suboptimal with respect to user happiness.)