Little dude was getting ready to attack my camera.
Although many spiders (including this salticid) only bite if provoked, this stance means they've been sufficiently provoked. If you see any spider lift their cephalothorax like this, it means they intend to bite. You'll see the same stance (often with the front legs lifted off the ground) in the gentlest of spider families, all the way up to tarantulas when you've got them scared enough to defend themselves from you. I had been playing with this spider for about 5 minutes, trying to keep him out in the open for photos, before he did this. At this point, I let him wander back under my stove where he wanted to go.
This so-called "Jumping Spider" can't really inflict much harm on a human with its venom, but spider bites frequently carry bacteria and can lead to secondary infection. Most of the thousands of different species of jumping spiders can leap many times their own body length. They're friendly, great hunters, and beneficial to have in the home most of the time.