I will testify to the effectiveness of the Zalman CNPS8900 Quiet Cooler...If your rig could house it. Having an all-copper conductor manages to keep my i7-6700k around 25C when idle.
I was actually hunting around for some low profile cpu coolers for quite a while and saw that list over on Bing (I prefer it to Google since it loads up automatically on my work PC) and it was a pretty helpful list actually.