** CORRECTION 6/7/2013: These are leaf footed bug nymphs, which have the two black spots and hang out in clusters. https://insects.tamu.edu/fieldguide/aimg65.html
I've posted these assassin bugs in the past, and they have appeared in the garden this year. I found a cluster of their offspring on a cluster of coriander seeds that I was waiting to dry so I could replant them or save for the fall. Assassin bugs prey on flies, caterpillars, beetles, and mosquitoes, so they are welcome inhabitants in my garden.