The only known person to have developed a spider sense was the 'Spiderman', commonly known for the ability to turn into a spider. It was a very small spider, and I could not see it until he got bigger and now he looks like a human.
Everytime Spiderman is in a great amount of danger, his head starts to glow like the sun (Only in the video game). He then either avoids the danger and lives, or is killed instantly and another spiderman is created. In history there have been only 265 spidermen, as they were all very clever when it came to identifying the spider sense.
Related to the 6th sense, includes the Children sense, which only Michael Jackson has at present.