My favorite landing page is the one for Buckyballs (http://www.getbuckyballs.com/). Thanks to it, I'm sure they moved a lot of product on the day Google doodled "buckyball".
Doesn't seem worse than any other company. I would reserve extremely slimey for companies that fuck their customers over, fucking with your competition is the name of the game ;) Example: http://news.ycombinator.com/item?id=1834976