Not really a mod, but if you have the time and patience to learn how to use it the Morrowind Graphics Extender can be used to achieve a lot of flashy effects that cant be done with the original Morrowind, That is, if you have a good graphics card. With that, you can also add "Distant land" to morrowind, which, like oblivion allows you to see far into the distance, even if it is a bit dodgy.