Nearly all the Ti lights are custom/semi-custom. Don McLeish makes the Ti PD, Orb makes a couple in Ti, CR2 Ion has a Ti I believe, Fenix has a new Ti version and I think Mr. Bulk had some Ti builds. There are probably more too - just do a search on Titanium here.
There are quite a number of threads about such lights and a lot of people who do those as mentioned in the post above. You might also search for the user names "Tranquility_Base" and "Morelite".
As a member for more than one year you should know how to use the search function before posting a question where the answer is to be found all over the place.