(I think you're correct in observing that many deserving questions aren't voted up, but the one you link to is not a typical example. In particular, any question that requires two pages of code in order to pose usually has not been well thought out or researched and shouldn't garner many readers.)
There actually is a badge to encourage voting for questions: Electorate. A couple of users have it already. Maybe as more acquire it others will get the point.
I recently raised this issue in an answer to a different question on meta, so I won't repeat those points here.
Other SE sites are discussing similar concerns. A few months ago @jrista on the Photography meta site provided a nice analysis along with a proposal to measure overall voting rates. It's worth a read.
In other meta exchanges (I forget exactly where), people have pointed out that it's psychologically easier to vote for answers than for questions. I have constantly to remind myself to return to each question in order to vote for it, even after I've been sufficiently engaged to answer it. Maybe the mods here can think of some gentle ways to remind or encourage people to vote for well-formulated questions.
That last adjective is helpful, I find: "well-formulated." It has been objected on some sites that few people can understand even a fraction of the questions. Well, I have that trouble everywhere, especially here. But I believe I can tell when a question is well posed, neatly and succinctly put, and invites an interesting or useful answer. I vote those up whether I really understand them or even sympathize with them. It's genuinely hard to come up with good questions and to express them well.
Finally, many questions here don't get many views. That's a shame. One of the most useful aspects of the SE sites is that you get a daily overview of the issues that are engaging people in the community. In short order you can get a larger sense of the things people are working on. Intellectual curiosity, if not professional diligence, would suggest that we all take a few minutes occasionally to read these questions rather than focusing only on the familiar subjects--and why not vote up the good ones as we're doing so?