The great thing about working from public WiFi spots is the people you can meet.

As I was waiting for the Facebook developers conference to start, I ended up in a cafe next to someone who knows as much as anyone about how to build an ecosystem of developers.

Dave Nielsen wasn't part of the early team at PayPal, but he was its first tech evangelist after eBay bought the company and ended up working with hundreds of thousands of developers.

These days he's helping Glam build out its developer platform, which the network of 600 women-focused Web sites unveiled this week.

Part of that is a widget extension that allows widget apps to work across the Glam network. Glam takes a cut for distributing them, then lets publishers and widget makers split the rest of the revenue from any ads they sell with them.

While social networks like Facebook and MySpace have had widely-reported difficulty monetizing their users, Glam is getting average CPMs over $1 because it's serving ads to publishers that have been pre-screened for its network, rather than to individual pages.

Nielsen says that widgets are a good fit for software-as-a-service technologies, and he sees a day where most software will be delivered over the Web in widget form for free, with software makers getting their money from support services.

Nielsen pointed out that PayPal was among the first companies to use a widget to help it virally expand its user base. The widget in question started out as an email hyperlink to whomever the user was sending payment to. That hyperlink was turned into a button. Several million users later, eBay bought PayPal for more than $1 billion. 

Guys like Max Levchin then took what they learned at PayPal and used it to start companies like  Slide, one of the two biggest Facebook app makers (along with RockYou).