When David Yang recently looked for a new apartment in Chicago, he took an aerial tour of the city.
As a 22-year-old on a limited budget, Yang couldn't afford to hire a helicopter for his visual inspection of Chicago. Instead, he turned to HousingMaps, a hack that combines craigslist real estate listings with city maps from Google Maps. It lets users pinpoint locations, along with one-click access to photos and descriptions, of dozens of available apartments in more than 20 North American cities.
"It's like flying around the city looking at real estate," said Yang, a consultant for Deloitte. "If I know where my friend lives, or I know where an El (train) stop is ... I can just zoom in and see what's convenient to me."
HousingMaps, created by Paul Rademacher, a 3-D graphic artist from Santa Clara, California, is just one of several innovative hacks giving users new ways to use information since Google launched its maps service. Google Maps offers detailed maps of nearly anywhere in the United States or Canada on which users can quickly zoom in or out.
These simple but powerful hacks are not exactly authorized. Google has not offered software tools and licensing terms for developers to work with its mapping engine and data. But the hacks nevertheless offer a compelling glimpse of what's possible when online data plays well together -- a major goal of internet-standards initiatives such as XML that, for the most part, are still a work in progress.
HousingMaps is an eye-opener, offering a simple and easy-to-navigate interface that lets home and rental shoppers take in a neighborhood of offerings at a glance, complete with locations, prices and, in some cases, pictures. Even with the extra data, maps rendered smoothly when we tried them on Thursday.
Hackers have also meshed Google Maps with sites like the photo-sharing service Flickr, Yahoo's traffic notifications, city transit maps and others.
Google said it doesn't comment on other websites.
But Stewart Butterfield, a Flickr co-founder, said he thinks Google Maps is a natural service for tech-savvy developers to want to use as the basis for experimentation.
"The main reason we're seeing it mashed up is that the implementation is eminently hackable, whereas few other similar services are," said Butterfield. "If you're a developer with a neat idea for mapping stuff, Google Maps is perfect, because all the data is accessible."
According to HousingMaps creator Rademacher, Google Maps -- as well as other web-based mapping applications -- are fairly simple to work with because they run inside a browser. Thus, he explained, a developer can easily access and manipulate the JavaScript to create a hack like HousingMaps.
Rademacher also said that while Yahoo's map service would have technically worked for his purposes, he chose Google Maps because it offered more features, including the ability to overlay information directly on the map.
HousingMaps helped Yang find an apartment he said he never would have looked at without being able to see its exact location relative to friends, bars and restaurants, and public transportation.
Others have employed it to create imaginary boundaries beyond which they don't need to bother looking for apartments.
"I knew I wanted to live within 10 minutes of downtown," said Kirk Duchow, who used HousingMaps to find an apartment when he recently moved to Denver from Atlanta. "I was just able to look at the map and figure out (which) area I wanted to live in, rather than having to get down deep and understand all the neighborhoods."
Of course, many online real estate services, including craigslist, offer maps for their listings. But in general, they only give map information one apartment at a time. HousingMaps, by comparison, simultaneously shows the locations of dozens of listings in a given city.
"It was certainly the best tool for (apartment hunting) online," said Duchow. "There are a lot of other moving sites, but you have to know a lot about the city for them to be useful.... Whereas with this tool, you can just look at the map and say, OK, that's about where I want to be."
Mischa Levin, a law student at Chicago's De Paul university, used Gregory Sadetsky's hack -- which mashed up Google Maps and traffic information, first from Yahoo and now from Traffic.com. It has been a daily timesaver.
"I check it every single morning before I leave," said Levin. "If I'm driving and if there's traffic conditions that are really bad, I'll take public transit. It shows traffic advisories, so if there's a Cubs game, I know the streets will be full of assholes, so I don't have to go there."
Levin said he's also a fan of another hack that overlays the Chicago public transit system on Google's map of the city. There are similar sites for Boston and New York.
"All these things are very, very helpful for avoiding driving," said Levin.
Another popular combination is Daniel Catt's Geobloggers, a blending of Google Maps with Flickr that displays the location -- within geographic areas on a Google map -- of pictures hosted on the photo-sharing service. Users plug the longitude and latitude of locations of their Flickr photos into Geobloggers and tag those photos with the name of the city within Flickr.
Geobloggers users can turn to a third site that automatically returns the longitude and latitude of any address entered into Google Maps.
For many people, like Chicago's Brian Armknecht, Geobloggers is a convenient way to see how his city is represented on Flickr.
"I like to ... take pictures around Chicago, and it kind of gives me a map of what territory I've covered and what I'm missing," said Armknecht. "I'm also using it as a way of connecting with other Chicago-area photographers."
Bryan Partington, who lives in Toronto, is planning a long cross-continent trip this summer, and is looking forward to posting pictures from his journey on Flickr and using Geobloggers to plot his movements.
"People should be able to follow my physical progress, especially between major centers," Partington said. "Also, when I'm done, and people look at my Geobloggers page, they will immediately see that I've been on this big trip, since my photos will be spread out all over the place."
