When I need this "torn page" effect, I use SnagIt. That's a program for
making and editing sceenshots, www.techsmith.com. You can make a screenshot
of the table, cut off the lower half and apply this effect to the bottom
edge. Then do the same with a screenshot of the upper half and combine those
two on the slide. But they will not be editable tables any longer.

If you need an editable table, draw a shape with top and bottom torn edge as
a freeform in PowerPoint, format it with background color and cover the
middle of the table with it.

Best regards,
Ute

Perhaps you can apply the technique found here to your table:
http://pptheaven.mvps.org/tutorials/tear.html.

Before you can use this tutorial you'll need to convert your table to an
Windows Metafile.  To do this, select the table. Edit > Cut. Edit > Paste
Special. Select Windows Metafile.

Be sure to save the original table before you start this process.

PowerPoint Responsibly

Sandy Johnson
Microsoft Certified Office Specialist (MOS PowerPoint)