The discovery of giant viruses has recast ideas on what constitutes a virus. Although diverse in many respects, all giant viruses have an extremely large virion (up to 1.5 μm) and genome (up to 2.8 Mb). Legendre et al. recently described a giant virus, Pithovirus sibericum, in 30,000-year-old permafrost, and now isolate a second giant virus, Mollivirus sibericum, from the same ancient sample. Despite its epoch-long freeze, M. sibericum remains infectious. Electron microscopy revealed a 0.6 μm spherical virion that releases its DNA through a 200 nm apex; viral DNA migrates to the host nucleus, but the virion factory is perinuclear. The 0.65 Mb genome does not seem to share recent ancestry with any other sequenced virus but, intriguingly, has acquired a large number of genes from other giant viruses and its amoeba host by horizontal transfer. More intriguing still is the detection of host ribosomal proteins within virions, which has not been seen in other viruses.