I know there are http://www.uesp.net/wiki/Morrowind:Lights that do not go out after XX minutes of use, but I can't seem to find them. Any hints?

the infinate time torches used by the guards have the id "torch_infinate_time" so you might want to add some using console

unfortunately there are no infinate light sources that im aware of that are actually for sale. You either need to steal them or hack them in.

The few infinate lights (in addition to the one i mentioned above) include:

1. Iron Candlesticks (Light_Com_Candle_01 and Light_Com_Candle_01_64; The first one has a larger light radius). These are the most common.
2. Bug Lamps, but they are pretty useless.
3. One of the silver candle sticks (light_com_candle_03_64). Small radius, but looks nicer.

These can be checked in the cs if you want locations.

Enjoy.. err being illuminated. punpunpunpunpun :facepalm:

That, or just carry stuff in inventory (I don't think time counts when just sitting in inventory). Place stuff as needed and pick up when ready to leave. When dropped, they give off light indefinitely.

My home in Bruma is lit up like times square. (lol)

Also Pilgrim's Lanterns seem infinite enough. If I got my math correctly they burn 999999999 / 60 / 60 / 24 / 365 = 31,709... years in real life...
You can find one at least from what is supposedly Furius Acilius' resting place in http://www.uesp.net/maps/mwmap/mwmap.shtml?centeron=Ebonheart. You must be able to levitate to gain access to the ledge where the lantern's at.

At one time I seemed to come across these lanterns, like, every day IRL, but I don't remember any other locations anymore. One should do fine though...

I've noticed the same as some poster above. It seems to affect the time whether the light source is in hand or not. If it's only in inventory, its time doesn't reduce.

Yes, definitely. And since I'm playing a Monk character, it's quiet appropriate for RP (outlander [Orc], pilgrim of sorts, bringing the divine Light to the peoples of MW...). I'd like to have it in hand at all times, unless unavoidable combat dictates otherwise...

Yea, plenty of hand held lanterns last so long they may aswell be infinte

Any candle, lantern or lamp that you find in the gameworld (not in a merchant inventory) and is lit, will stay lit forever.
I prefer blue and red lanterns.

All lights are infinite when placed on the ground or used by an NPC. But only a few, like the one Archmagister Nelacayne mentioned, are infinite (or essentially so) when used by the player.

If that's the case, then why would the OP want such a torch I wonder? I prefer simply using night eye constant effect.

I think it was in Tel Fyr that I found a bug lamp, across from Divayth. Or maybe the tower in Sadrith Mora.