It seems that PADI (the Scuba Diving certification company) have setup something in SL, from the looks of it, its about e-learning. As someone who is Open Water Certified, I know there is quite a bit of classroom work to be done before you even get in the water, so I can see how SL could help here.
What is strange is that they seem to have setup right next to virtual Manchester of all places!!
Here are some snaps..