Spider-Man's origin, slightly retconned.

[neatoman]

You remember that radiation device that created the radioactive spider? Turns out it has a name now, "Isotope Genome Accelerator". It was described by Doctor Connors in the latest issue as "... Often used to transmutate characteristics of one organism on to another."

Basically, it's been retconned from simply irradiating a spider, to now having done exactly what it was designed for.