We quite rightly hold inventors in high esteem: the brilliant people who make leaps of imagination and engineering that the rest of us can't even dream of. But did you know that half of all registered inventions "arise unexpectedly"? That is, the final product or breakthrough is not what the inventor was originally looking for.

Ars Technica's Annalee Newitz reports on a book called Inventology by American author Pagan Kennedy, who analyses a 2005 survey of patent holders that found 50 percent of patents came as a result of "serendipitous" processes – in other words, happy accidents. Which is all well and good, but can these happy accidents be fostered or encouraged in some way to give us more inventions?

According to Kennedy's research, people can even invent new and innovative products when they're not actually trying to invent anything at all. The biggest source of inspiration comes from the intended audience - the people who are actually going to be using the finished product, and two-thirds of patents arise from some form of collaboration, the survey found.

"As people dredge the unknown, they are engaging in a highly creative act," Kennedy explained over at The New York Times. "Some scientists even embrace a kind of 'free jazz' method… improvising as they go along."

As American Nobel Prize-winning biologist Martin Chalfie once said, "I've heard of people getting good results after accidentally dropping their experimental preparations on the floor, picking them up, and working on them nonetheless."

Kennedy proposes further study into the people who have a tendency to make serendipitous discoveries, but defining those terms and pinpointing the right data has so far proven to be extremely difficult.

It's something that University of Missouri scientist Sanda Erdelez has been looking into for decades. In a study of 132 people published in the mid-1990s, she found those people could be split into three groups - non-encounterers, occasional encounterers, and super-encounterers - in terms of stumbling across unsought surprises.

It appears that there's something about our character that affects how many discoveries we make, but Erdelez says it's partly due to which category we think we fall into in the first place. As she explains for The New York Times, trying to define the particulars of serendipity so we can effectively 'game the system' will be almost impossible, but entirely worth it:

"[E]ven if we do organise the study of serendipity, it will always be a whimsical undertaking, given that the phenomenon is difficult to define, amazingly variable, and hard to capture in data. … The journey will be maddening, but the potential insights could be profound: one day we might be able to stumble upon new and better ways of getting lost."

But back to the assertion that half of all inventions are products of these serendipitous discoveries. Turns out, some of the most well-known inventions of our times happened by accident. Here are some of our favourites:

  • Microwave oven: one of the most well-known examples, the microwave oven was invented by Percy Spencer after he noticed the radar set he was working on melted a chocolate bar in his pocket. The first food he intentionally heated up with microwaves was popcorn.
  • Coca-Cola: plenty of foods, drinks, and drugs are invented by accident, including one of the world's most famous beverages. Confederate Colonel John Pemberton originally happened upon the recipe as a tonic for his nerves and it was first sold as a pain-reducing medicine.
  • Teflon: the result of a serendipitous discovery in the laboratory, the non-reactive, non-stick chemical was chanced upon by chemist Roy Plunkett while he was experimenting with refrigerants. Plunkett spotted the potential of the substance, and the rest is history.
  • Penicillin: another famous example of an accidental discovery, penicillin was found by Sir Alexander Fleming while he was busy searching for a 'wonder drug' to cure disease. Only when he noticed mould growing in a discarded Petri dish was penicillin actually discovered.
  • Post-it notes: no one set out to invent Post-it notes. Spencer Silver is credited with their creation, but he was actually looking to invent a super-strong adhesive. What he accidentally invented instead was a super-weak one that would eventually be used on pads of sticky notes.