Displaying a Time-based Number

[nerdcore]

I'm looking for a way to display a date- or time-based number in an Impress presentation. When a slide is displayed, it needs to have an ever-increasing number displayed. This number is based on the current day when the slide is displayed, so if I show the presentation today, then again tomorrow, the number will be larger tomorrow.

Can anyone suggest a way to go about doing this? I wasn't sure if this should be posted in the Macros forum instead, as I'm not sure if a Macro is what's needed, but it does need to be in a presentation.

Any help would be greatly appreciated.

Thanks,
--Mike