I strongly agree with Amy regarding Chinese Evergeens aka Aglaonemas. They have very nice colors on large leaves, the red is really spectacular although it requires a bit more light than the others. Also, syngoniums come in a range of green colors, as well as cream, pink, and maroons. Also, sanseverias have very interesting color foliage and do well in low light. The have leaves with yellow and cream varigation and stripes. I hope this is helpful.