Two words: beer bike. Actually, "bike" isn't quite right--it's a mobile, pedal-powered bar that drinkers guide through the streets of Amsterdam. Have a look:
Outside of Amsterdam, what other city do you know off-hand so closely associated with bikes and beer? Portland is a no-brainer for this technology! Would not a tour of the city be much more entertaining with a pint? How about a mobile beer fest, with a flotilla of roving beer bikes? Heck, even Trimet might be able to hold off on the next round of fare hikes if they ran a few of these along key routes (every third 14 bus, down Hawthorne, say). The opportunities are limitless.
I sense a business opportunity...
(Though I got wind of this contraption thanks to recent news that a couple of recent accidents have jeopardized these even in the Amsterdam, so maybe it's not the safest business model.)