Express Bus Lane to Seattle
Express Bus (way cheaper and easier to do than high-speed rail) to Seattle. Set aside a dedicated lane for bus service between the two hubs and watch transit (and business connections) take off. Bonus idea: Specific buses that require all passengers to be nexus approved, meaning swifter border crossings.
Already in place on the East Coast: http://travel.nytimes.com/2010/07/25/travel/25Prac.html?adxnnl=1&hpw=&adxnnlx=1279735270-6prOYEpRjwtJ5CN5jXa6mA
Outside jurisdiction. Inter-regional transit is a great idea.