Common varieties of borage have prickly leaves and small pink/purple/blue flowers (colour variance occurs upon the one plant). The flowers can be put in salads, cordials, and beers. Borage is reputed to give the drinker courage, making borage beer reputedly a drink to have before going into battle. (for beers, see Brewing)
Did you know?: Borage leaves are supposed to have high levels of magnesium, and when put on a fire are supposed to make a minor fireworks display. I've tested small quantities of fresh borage leaves, but no sparklies. Perhaps whole branches of dried borrage on an open fire would work?
see also: other herbs