Excel XP, Windows 2000

I've searched through the group but don't see what I'm looking for.

I have two groups of 4-character text strings. Each group has five
different strings. I need to find out the possible combinations of one from
group A and one from group B.

Example:

Group A: KMNN,KONN,RGNN,RONN,OONN
Group B: KDNN,OPNN,OQNN,OTNN,WDNN

One combination would be KMNN with KDNN. Another would be KMNN with OTNN,
and a third would be RGNN with OTNN.

How can I come up with a list of all possible combinations?

Thanks for your help.

Allison