Animal venoms contain a huge variety of bioactive molecules—namely, toxins—with an almost combinatorial spectrum of biological activities. Since ancient times, venoms and individual toxins have attracted much attention, first as weapons against enemies and as active components in folk medicine, and nowadays as tools for functional and structural studies of essential membrane receptors and as prototypes in the design of new drugs [1]. Indeed, the diversity of venomous animals and the targets on which the components of their venoms act is extremely wide. Sea anemones, jellyfishes, cone snails, centipedes, spiders, scorpions, ants, bees, fish, frogs, lizards, snakes, and many other animals can produce venoms that are cocktails of highly toxic compounds. The spectrum of activity of these compounds is quite broad, and such activity is associated with the action on the basic functions of the prey which these poisonous creatures hunt or predators from which they defend themselves. These functions include breathing, mobility, cardiac activity, muscle contraction, nervous activity, pain signaling, blood coagulation, and integrity of tissues and individual cells, including blood cells.