Inspired by http://p5art.tumblr.com/post/77911162613/circles-crossing-a-quickie-code-here

crossing-circles.clj

(ns crossing-circles
  (:use quil.core))

(def θ (atom 0))

(defn circles [sw]
  (stroke-weight sw)
  (doseq [i (range 1 15)]
    (let [dr (* sw 2.5)
          r (* i dr)]
      (ellipse 0 0 r r))))

(defn setup []
  (smooth)
  (stroke 0)
  (ellipse-mode :center)
  (no-fill))

(defn draw []
  (background 255)
  (let [amplitude 200
        phase 250]
    (doseq [x [(+ phase (* amplitude (sin (radians @θ)))) 
               (+ phase (* (- amplitude) (sin (radians @θ))))]]
      (push-matrix)
      (translate x 250)
      (circles 15)
      (pop-matrix)))
  (swap! θ + 10))

(sketch
  :title "looking up"
  :setup setup
  :draw draw
  :size [500 500]
  :renderer :java2d)