I recently found these guys on my tomato plants. They like to group together but I'm not sure if they're beneficial or harmful...
Pretty pink APHIDS. Aphids are one of the most common of garden pests, and come in a wide range of colors: pink, apple green, gray, brown, black, spotted, yellow with black 'stockings', red, and probably more.
Get after them with your fingers or a sharp spray of plain water.