Andrew Mason’s talk at Startup School 2010 included a slide that really blew my mind. The slide wasn’t about Groupon (Andrew’s company), it was about Meetup.com.

Andrew heard Scott Heiferman (CEO of Meetup.com) describe the initial version of Meetup.com as a matrix of cities and interests. He put it in spreadsheet format and here’s how it came out:

It doesn’t matter how many rows or columns – it works at all scales. It’s such a simple representation of what is ultimately a simple idea (meeting up with people in your city who share a similar interest), but it could just as easily been diagrammed in a complex way.

I’ve come back to this slide over and over for inspiration when thinking about new concepts or product ideas. It’s a great exercise in clarity. Can I boil down the idea into something as simple as a column and a row?