Yep...

amazon.com has two rows of navigation on top:

Here are the examples of retail e-commerce sites, which are "more complex" than amazon.com

- http://www.macys.com. - 4 rows

- http://www.jcpenney.com/ - 4 rows

- http://www.gap.com/ - 3 rows

- http://nordstrom.com - 4 rows

and the winners are:

- http://www.costco.com/

- http://frys.com/

5 rows of navigation one on top of the other

....go get lost!

Five rows of navigation boggles the mind.