For a small 100 residue protein there are 20100 possible sequences. This number vastly exceeds the number of atoms in the universe. Therefore, despite billions of years of evolution, nature has only sampled a tiny fraction of what might be possible. To explore structures and functions beyond those sampled by nature, we designed libraries of synthetic genes encoding millions of novel proteins that share no ancestry with those that arose in nature. Many of these new proteins fold into stable structures; and many bind metals, cofactors, and reaction substrates. In some cases, a novel protein can sustain cell growth by functioning as bona fide enzyme catalyzing an essential biochemical reaction. In other cases, novel proteins enable the growth of living systems by providing unexpected non-natural functions that rewire gene regulation. We have also discovered novel proteins that perform functions that are not biological and were not selected by evolution. These include novel proteins that catalyze the formation of semiconductor quantum dots. In a sense, libraries of novel proteins represent a step towards the development of non-natural proteomes. This presentation will describe some of the novel functions encoded by an artificial proteome.