In the latest episode of Mental Floss, Derek Muller is on loan from Veritasium to dish out two dozen unintended scientific discoveries, including a few you've probably heard of (like penicillin*) and a bunch you probably haven't (like Viagra).

*While we're on the subject of penicillin, there's more to its discovery than you've probably been led to believe. In fact, Alexander Fleming himself termed his importance in the development of therapeutic penicillin the "Fleming Myth."

[Mental Floss]