These gable ends of shophouses along Jalan Besar have nicely rounded mounds. Based on Historic Chinese Architecture of Singapore's (https://nanyangtemple.wordpress.com/category/2-visiting-guide/) article on the kinds of gable ends depicting the five Chinese elements (wood, water, metal, earth and fire), their rounded top would depict the metal element.
This interesting gable with a seemingly almost detachable "knob" at the tip of its apex (so the gable wall looks like the lid of your coffee mug) is at Kitchener Road. Using my favourite "knob" guide/https://nanyangtemple.wordpress.com/category/2-visiting-guide/, I can only hazard a guess that it depicts the wood element, rather common for old shophouses. Pictures taken June 2014.
Gables of New Bridge Centre (above and below). Although relatively modern, the roof ridge ends with a squarish knob at the gables -- which according to feng shui, would seemingly depict the earth element. Pictures courtesy of Walter Lo.
Gable with Hindu motif belonging to a Chinese shophouse next to the Sri Mariamman Temple at Temple Street. Picture courtesy of Walter Lo.
Twin peaks belonging to Yueh Hai Ching Temple at Philip Street. This temple is the oldest Taoist temple in Singapore, constructed between 1850 and 1855, rebuilt in 1895. The gable ends seem to me to be of the earth element, or maybe fire (judging from the two pointed ends on each side of the mound.)
Old gabes II: http://bitspiece.blogspot.sg/2014/11/old-gables-ii.html