The great enemy of quantum information is decoherence, through which a quantum system quickly becomes classical. Trapped ions form an ideal medium for quantum information as they can be well controlled using laser beams while being relatively well isolated from external noise sources. I will show how ensembles of cold ions can be used as quantum memories either to store the quadratures describing intense light beams (continuous variable regime) or for very long lived qubits, based on the principles of topological protection.