I'm sure this conversation has been had on news.yc, but how do you account for ugly ass sites like myspace, plenty of fish, and craigslist?
Sure. But the word you're looking for is functional, not ugly. The ugliness is just a side effect.
Craigslist was criticized for being too plain from the moment it was built. But it's buried a lot of better-Photoshopped competitors.
Dove is using this idea in their "Campaign for Natural Beauty" (http://www.dove.us/#/cfrb/) . The models aren't ugly, but they also aren't the usual perfect-looking models.
When I was in grade school, I remember there were anti-smoking and tobacco posters on the wall of severely aged, sick looking people along with some text about how "chewing cost me my mandible". Those were examples of actual human ugliness, and they worked.
So that's all to say, ugly could be part of your message. Which isn't really a novel idea.
What's more interesting, in my opinion, is when something seems bad from a usability standpoint and still succeeds. plentyoffish.com fits under this category.
Facebook has made serious inroads largely due to better design (in terms of aesthetics and usability) than myspace.
Plentyoffish, craigslist, and Wikipedia are ugly ass sites that seem pretty much unassailable though.
The original walkman was ugly as sin, but it was cheap and reliable. Had it been beautiful, it would have been even better, but it couldn't, without costing more.