As much for my edification as anyones:
Want to get at just a few points within the pointcloud extension? A with query will get you there:

DROP TABLE IF EXISTS points;

CREATE TABLE points AS
WITH
-- get me some patches (our lidar points are stored in patches)
patches AS (
  SELECT pa FROM test
	LIMIT 2
),
-- Now, I want all the points from each patch
pa_pts AS (
  SELECT PC_Explode(pa) AS pts FROM patches
)
-- OK. Can I have that as standard old points, PostGIS style?
SELECT pts::geometry FROM pa_pts;
--k thanx