In the US anyway, given that people or companies have been sued for the following things:
- seat belts that could not be disengaged underwater by an intoxicated person who drove a car into Galveston Bay (another person in the car was able to free herself)
- cookies that contained trans-fat
- beer that did not produce luck with the ladies (and gave the consumer a hangover, to boot)
- potential confusion between Tony the Tiger and Exxon's tiger logo
- that robbing a convenience store with a shotgun was caused by your organization's sexual and disability discrimination
- suing yourself (!) because you violated your own civil rights and religious beliefs when drunk
And the "Top Shelf" circumstance for getting sued:
- that the large breasts from your strip club's dancer caused whiplash and mental anguish
So, yeah - I think you can get sued for something you say here, as well as for pretty much anything else you do in life (at least in the US). As far as the lawsuit being successful...
Numbers 1 and 5 were awarded damages (which may have been reduced or thrown out on appeal).
So be careful what you say, and be careful how you look at your neighbor.
That said, I think you're more likely to get sued for downvoting someone here... Some people take it personally.