Tibetan is the language of Tibet and of Tibetan Buddhism. The Dzongkha language of Bhutan is written in the Tibetan alphabet.
There is limited Tibetan support, including fonts and keyboard layouts, in some versions of Linux.
A very extensive collection of Tibetan Buddhist scriptures is available from the Asian Classics Input Project for free download. The project has raised money to pay Tibetan monks living in India to do the data entry, and has provided the computers at no charge.
Tibetan is encoded in Unicode in the range U+0F00-U+0FFF. Fonts containing Tibetan include Arial Unicode MS and Code2000.
[IndLinux] is working on a Dzongkha distribution of Linux.