Jumping spiders are among my very favorite animals, especially the brightly colored ones.   They look (and behave) like they're full of personality -- highly visual and alert, active, and seemingly unafraid.   They're aggressive predators that act like big cats: stalking prey and attacking in a leap or a rush, then biting and wrestling it into submission (sometimes they go for insects much bigger than themselves).   These photos show an adult male spider -- identifiable as such by his thin abdomen and large pedipalps under the 'face' -- that is probably Thiodina sylvana, a small species (maybe 6-8 mm long).   The spider came from Arizona (although I took the pictures in a colleague's lab at the University of California, Riverside).
            Images of other jumping spiders are here, here, here, here, here, here, here, and here.