Progress Display on bars

Is there a way I can show the physical progress % on the bar?. I have a baseline schedule and I dont want to update it, but I just want to show the physical percent complete in some graphical way on the activity bar, either a shade or a line on top of the bar. Say for example, an activity of duration 10 days(from 1Jan06 to 10Jan06 is 30% complete, I just want to show a bar of 1Jan06 to 10Jan06, with shade or colour from 1Jan06 to 3Jan06, irrespective of whenever the start date was or remaining duration will be.

I know it sounds a bit weird, but my boss it needs it that way.

Thanks
Rajeev