My ultimate favorite burger is the Banzai burger at Red Robin. It's a beef patty with teriyaki sauce and pineapple. As mentioned in my Eastlake blog post, I tend to order the petite/kid size since they are sooo filling. The fries that come with it are pretty amazing too.
Lunchbox Laboratory is my new favorite burger place in Ballard at 7302 15th Ave NW. They have burgers so big they can feed three people easily. There are at least 7 different types of meat to choose from, plus more kinds coming soon to the menu, 10-15 cheese varieties, besides bacon there are 6 other toppings, and over 20 different mayonnaise, mustards, aioli and sauce options! I've only been there once so I can't pick a favorite burger yet. I must keep trying more of them before deciding! Here's an example of how great these burgers look: (Sidenote: When searching on the internet for this restaurant, I also got a link to the Futurefarmers project site with a lunch box "prototype for a potentially distributed research tool that would be sent to schools such that young scientists could do primary screening of a collection of algae strains"!It's a very cool collaboration between the National Renewable Energy Lab and the Futurefarmers team, on display at the Museum of Modern Art.)