Delicious geohashes … mmmm … tagging *drool*

Since I got a new toy for Christmas, I’ve become interested in geolocation and the fun things you can do when you have an internet-connected GPS-enabled device in your pocket. I’m also a compulsive delicious tagger, so I quickly discovered the existing practice for geotagging delicious bookmarks.

Essentially, this seems to be: add the tag ‘geotagged‘, along with the tags ‘geo:lat=X.xxx‘ and ‘geo:lon=X.xxx‘, where the X.xxx‘s are the latitude and longtitude numbers that are likely to come straight out of your GPS, in decimal degrees (WGS84).

This is all very nice, but the problem with tags in this format is that there is no easy or efficient way to use them to retrieve all items tagged for a particular locality. Sure, if I’m standing right on top of the Eureka Tower at -37.821362,144.964213, I can search for tags geo:lat=-37.821362 and geo:lon=144.964213 to find all the geotagged links for that exact location, but what if I’m standing 50 metres across the street looking up at the tower and want to search for links near my current location ? Continue reading