Since being invited to contribute to Comet Daily, I’ve been thinking about what to do with my opening post, and I can think of nothing better to get things going with a bang than to talk about the antics at Hack Day ‘07 here in London. Hack Day was a gathering of around 200 hackers sponsored by the BBC and Yahoo, in which everyone was given 36 hours to hack together the most amazing mashup they could muster.

There were 62 hacks in all, some more outlandish than others. The other guys on our table created Fruitr, a Flickr-powered fruit recognition engine, and there were airships, mapping apps, and even one entirely paper-based hack that had the audience in fits. What struck me though, was that none of the hacks were event-driven (except ours, naturally!). The prevalence of APIs everywhere is great, but are web service owners missing a trick by only making their data available via REST/SOAP/RSS interfaces?

Take twitter, for example. I can get an RSS feed of the latest twitters from everyone, but seeing as there are so many, I have to refresh the feed at a rate that borders on denial-of-service to guarantee that I’ll capture all activity. So we thought: let’s do something with Meteor, the open-source perl-based comet server, to demonstrate what event-driven interfaces can do.

The event had wifi provided by BT Openzone running from about 15 access points around the hall, so we set up sniffers to capture all the traffic going over the air, and sent it to a Meteor controller script that we knocked up in PHP to inject packet stats into Meteor. We then did an interface in Javascript/XHTML/CSS, deployed the Meteor javascript client, and were able to see in real time what everyone in the room was doing on the web. Suffice to say there were some fairly bizarre protocols flying about.

Anyway, here’s a screencast of our demo:

The left column shows a ranked list of protocols in use by number of packets, so HTTP, IMAP and SSH were always pretty close to the top. The second column shows the IP addresses of people accessing the Meteor demo and their user agent (that’s from an access log monitor daemon, rather than any data from the Wifi). Finally the right hand side has a world map with flashing dots showing the targets of the traffic from the Hack day hackers on a Yahoo Map, our token attempt to work BBC/Yahoo APIs into our hack!

The event itself became infamous for the lightning strike that hit the building. I was watching a brilliant talk on Yahoo’s new FireEagle project, and suddenly there was a loud bang, then a rising screaming noise (exactly the sort of rising screaming noise that precedes a big explosion, according to Hollywood), then after a couple of seconds of silence, all the fire control vents in the roof opened. This was a particular problem because it was pouring with rain, and two hundred laptops and their attendant hackers started getting rained on.

However, if you’re a hacker, the solution to this kind of incident is quite simple - it’s raining, so you need an umbrella:

Lightning is, of course, a push technology, so maybe nature was trying to tell us something. I’d also like to personally congratulate the person who tried to download Debian via my GPRS connection that I kindly shared during the wifi outage. I’ll be sending you my phone bill