i've seen a corprus stalker underwater next to some bandit cave. it kept respawning there too. i both killed it underwater and lured it out on land before killing it to have fun with it.

As for fish on land, i've seen a dreugh on top of a medium size rock barely above water somewhere next to vivec. it moved around as fast as it did underwater if i recall correctly.

the wierdest thing i have seen in this game is when i saw a rat in the water. it was several feet deep in there but it wasn't moving i thought it was dead but i went over and killed it. it was odd.

Slaughterfish and dreughs on land seem to be quite common, is that why Bethesda are introducing a land dreugh in Oblivion?

And I have seen giant golden saints around, anyone know if they are a glitch or is there a way to find them?