I used to get them when I was a kid, and not I can recreate nice healthy ones (without over exposure to unhealthy UV rays, not that I see much of those anyways).
They are really easy to create with a finishing brush, a fine point eyeliner brush, and a powder eye shadow, like MAC's Texture ($15).
I swiped this under the running faucet to get it just wet enough to pick up colour. As you can see with the finishing brush damp the hairs clump together to help leave perfect little dot shapes on the cheeks and across the nose.
To add more precise freckles I dampen my fine point liner brush and randomly place more freckles all over.
I still need more practice, but it is a great technique to play around with. At first I thought they looked a little too unnatural so I added a little bronzing powder over my cheeks to help smooth everything out.
You're really not supposed to wear your sunglasses on your head because it stretched out the arms, but I plopped 'em up there to show that I was ready for some sunshine!