Well a run on sentence is a sentence where you read and read and read and read and you then run out of breath and it seems like it's going to go on forever and ever and then it starts to piss you off, then you think it should be a paragraph not a sentence so you think the writer has horrible grammar and you would rather have them write a sentence like dis cuz it lookz kool because run on sentences are really really annoying.

The big car was driving down the road, and it broke down, and then the driver came out and fixed the car, and then the driver drove to the supermarket, and then he picked up some salami and taco shells, and then the driver went home to his wife because he didn't really know what to do next, so he just kept driving home until he got home, and then he put the salami and taco shells in the fridge and then he made dinner and then he went to sleep.

gawd ... i am hearing a valley girl!!! eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeYAuGH!!!! the best in fiction i think is.. "this one time at band camp..."

I am not sure if this is what you are looking for for an example of a run on sentence but I seem to feel that the longer that I keep typing this answer that the sooner I am going to come to the point where this is going to become a run on sentence and you can be the judge of when such a point has made itself become overly evident to you since I surely would hate to disappoint anyone when I am trying to prove a point or otherwise try to provide a useful example especially when such an important undertaking is underway which really proves the point that we really must take it upon our selves to determine the proper points when we are not making a conclusive statement and actually we are just going on and on without any intention of stopping which in my opinion would constitute the beginnings of the ever dreaded grammatical occurrence of the run on sentence which certainly does not know when the correct time is for it to finally end as if that could be a possibility which eventually starts to fatigue the reader and makes them just hope and hope that finally the sentence will end but the most tortuous aspect of such sentences is that they can be interspersed amidst other sentences in paragraphs which totally obfuscates the moment at which the dreaded sentence will finally end hence bringing relief to everyone that has suffered so long whilst reading this.

one that goes on and on