The first public playthrough of one of the first UT2600 betas by ZeroPage HomeBrew Video Gaming.
Playthrough by M3MB3Rrr for Military Games-themed Atarian episode (Hungarian, subtitled).
"There's an Unreal Tournament demake for Atari 2600 you can play in your browser" on PC Gamer.
"UT2600: Demake de Unreal Tournament" on NeoTeo (Spanish).
The complete soundtrack for UT2600 is available for streaming (and download) on SoundCloud. Apart from the title track and the individual in-game tracks, abandoned sketches are also available.
For more information on the creation of UT2600's soundtrack, you can read this article on the composers website.