The talk will give an introduction to a new wealth of phenomena in the context of ultracold gases just above the condensation limit. We will start with the creation of ultracold plasmas and discuss how they can become laboratory examples for strongly coupled plasmas so far only known from astrophysical objects. As a second topic we will pay closer attention to possible interaction of cold atoms when some of them are Rydberg excited. This leads to the phenomenon of interaction blockade, i.e., only one atom can be excited. Finally, we will discuss the formation of long range bound structures in the ultracold gas, such as Rydberg molecules. Favorable circumstances allow the formation of molecules even under repulsive interaction of Rydberg and ground state atoms.