Venomous cone snails have been a gift to biomedical researchers. Over the past 50 years, scientists have isolated compounds from these predatory marine animals that do everything from stop pain to protect cells during a heart attack. Now, researchers have isolated a cone snail compound that does something unexpected: It puts mice to sleep. All of these compounds belong to a group of ion channels modifiers known as conotoxins. In the wild, the snails use these toxins for capturing prey, and typically when researchers inject them into mice, the rodents either have no response or become paralyzed. In the new study, published this month in Toxicon, researchers isolated and sequenced 14 novel peptide toxins from the venom of the cobweb cone, Conus araneosus (pictured above with its dissected venom gland). When they injected five of them into mice, one put the rodents to sleep for several hours, whereas the others had no effect. The team says the discovery expands the range of therapeutic uses for conotoxins, and could lead to drugs to treat sleep disorders.