What timing, as I was about to work on a simple webservice to convert postcodes to co-ordinates and was thinking about storage Heroku announce Beta support for MongoDB.

Created the app, writing the script to port to postgres table to Mongo's document-based structure then may either use Sinatra or Node.js to provide the webservice.

Q: why build such a service?

A: all UK postcodes are copyrighted by Royal Mail so if you want to translate those to x & y values you either have to pay someone to buy the data or pull it off something like openstreetmap. I opted for the first, and with 76k of records in one table Mongo's the leanest & coolest solution.

Thanks Heroku ;-)

update

built the webservice, ported the data from postgres to mongohq and it returns valid json!

try it out => Sinatra GeoCoding Service

e.g. EC2 => [{ "postalcode":"EC2", "latitude":"51.53701514", "longitude":"-0.0832304" }]

Update 2

next up replacing that awesomely huge table with geokit, getting it right second times a charm ;-)