Dark grey and deep red, Ohia gets its name from the colors of the blossom of the ohia lehua tree in Hawaii and cooled lava, in which ohia is one of the first plants to take root. Whenever we visit my wife's folks on the island of Kauaʻi, we try to get up to Kokeʻe and get refreshed with the mountain air and life that thrives there, including ohia.
Underground is a clean monochrome design with red details originally done in two columns. The Tiki implementation has default column padding and margins set for two columns, but of course all three columns can be used if desired. In this case, the margins and paddings can be modified accordingly.
Ohia, released under an LGPL license, can be seen at zukakakina.com/Ohia and downloaded here. The Underground demo is at zukakakina.com/Underground and its files are here. Undeground is released as a derived work of the original, which is licensed Creative Commons Attribution 2.5, so to comply with the terms of that license, please do not remove the small link to Styleshout.com in the page's bottom bar.
These both use the *litecss layout method, and fully implement all TikiWiki 2 features.