This is what I use. Seems to do a great job. The software is pretty good also!
http://www.extech.com/instruments/product.asp?catid=48&prodid=595
Although those are interesting products, I need a micro-controller to measure AC line voltage and current.
I have a couple of current clamp meters (as seen in the first video, one old junk and a decent new one) that work well enough. The goal is to have current measurement integrated into my project.
I expect that across the forum, members have used various approaches to integrate mains current measurement directly into their boards. I am hoping those members can enlighten me on their approaches, as well as things to watch out for, or how to mitigate problems.