Cooling atomic gases to nanoKelvin temperatures has revolutionized atomic physics. At nanoKelvin temperatures, new physics emerges: Bose-Einstein condensation, quantum reflection, strongly interacting gases. At nanoKelvin temperatures, the atoms are so cold that they can easily be manipulated by electromagnetic fields. This has led to miniaturized atom traps or atom chips, and offers a new perspective for atom interferometry. Recently, Bose-Einstein condensates of molecules and fermion pairs have been created and show behavior analogous to electrons in superconducting materials. A new form of high-temperature superfluidity has been discovered. In the future, we plan to use ultracold gases to create designer matter, i.e. to realize new forms of matter in the laboratory which have been discussed as model systems for many-body phenomena, but have not been observed in nature.