I just want to point out that the McDonalds coffee case was not as frivalous as people make it out to be. (Someone mentioned it above) What happenned in the case was that McDonalds used to heat their coffee over 180F degrees (because they didn't want their coffee to get cold for a 7 minute drive home) which at that temperature is instant 2nd-3rd degree burns. McDonalds got sued for endangering their customers.
It doesn't matter how hot the coffee is....if you drop it on your lap and it burns you then it's your own fault in my opinion. People don't generally order a cup of coffee from McDonald's expecting that it will be cold when they drop it on their lap.
In response to the main question: No I have never been sued. I have sued someone else before though and won my case. This guy shot me in the eye with a BB Gun and it ruined the vision in that eye for the rest of my life.