Self alignment tool?

[OptionZero]

http://www.racerpartswholesale.com/smart1.htm

Smart alignment using bars and strings and, presumably, built in readings.

anyone heard of this, and is it a reliable/accurate tool?

Given that alignments (good ones) can be damn near $100 or more, and the more adjustable parts you throw on your car the more aligning you need to do to make it all worthwhile...is that thing any use?

EDIT:
Found this: http://www.zilvia.net/f/showthread.php?t=76944&highlight=smart+strings

[SpeedMonkeyInc]

I have used the string method with good results. I used four jack stands, and a measuring tape. I just made sure each side was the same length so it would not throw off the results. Worked great! For camber, I used a level, put it flat on the ground and measured the gap to the top of the tire.
I am sure the $100 gizmo is easier and very consistant. But I didn't plan a head and order the gizmo in time for when I needed it, so I just rigged it.