I've never cast the spell Hypnotic Lure, but my gadgeteer will use the Lava Lamp regularly when battle starts and nothing is within range of his weapons. At a high level it is great for diverting the attention of many monsters (some that I would never have thought to fall for the "watch the flashing light" trick). If you put it reasonably close by they will walk/fly to the lure and sometimes face it with their backs to you.
* hits flying creature FROM BEHIND *My money is on Cure Lesser condition simply because I never take the time to use it.
BTW the lure works on 2-year-olds as well - my son loves to watch the "sun" appear in the middle of the night!