Grand Unifying Guesses/The Dark Tower

The Dark Tower (and its Beams) takes a different form in every universe. Some of these include:

• Haruhi Suzumiya, obviously.
• Azathoth, who lies in the centre of infinity, holding and creating the universe.
• The Planet Mildchilda, but the Infinite Library especially.
• The Heart of Kandrakar
• The Starborn Gem
• The Door To Revolution
• The Door Of Light And Darkness
• The Door Of Truth
• The Gate Of Truth
• The Galaxy Cauldron
• The Star Road
• The Eye of Harmony
• The Monarch of Pointland (she takes up her entire universe and thus must be the Dark Tower)
• The Infinite Clock, the World Tree, and the Sky Tree
• The aforementioned Tommy Westphall.
• The Submachine Net
  • Does that make Murtagh Roland? Or Flagg?
• The Portal Stones
• Tanelorn
• Callahan's Crosstime Saloon
• That fish shop. You know the one, the one they opened on Dagon Street...
• The fractal key
• Rupert Murdoch. This would explain a lot.
• Oban
• The Gates of Oblivion
• Spectra
• The Pillar of Cephiro was the Dark Tower until Hikaru made it so Cephiro was supported by the people of Cephiro.
• The Ark and the Halo Array
• That Gate The Gatekeeper is always going on about.
• And that Other Gatekeeper, too.
• The Portals from Spyro.
• The Instrumentality.
• The Internet in Real Life has the Tower's ability to bridge between realities.
• The Grand Master Key
• People's imagination, and to an extension, Imaginationland.
• The Jewel of Judgment, and by extension, the Primal Pattern. Depending upon interpretation, this may be reversed - the Tower could simply be an image of the Pattern.
• Witches
• The Heart of Ponyland
• And that other gatekeeper and key master.
• The Shards of Adonalsium. Hoid is busy making sure this version of the Tower doesn't break any further than it already has.
• Mt. Aleph.
• The Triforce, with the various Sages/Temples guarding the Beams.