dude, i recently had to make a progress bar for a tool that could take anywhere from a few minutes to a few hours to run. in the end, i just showed the total number of tasks to complete, the current task it was on, and the average elapsed time of the last 10 tasks. the end user loved it. i included the bar as well, but it just kind of jerks around. i found the main thing was the user wanted to see the number of tasks and what task it was currently on more than anything