Should I store latitude and longitude as strings or floats (or something else)?
(I\'m using activerecord / ruby on rails, if that matters).
Update:
Mysql
If you need to do more complex geographical calculations, you can investigate PostGIS for Postgresql or MySQL Spatial Extensions for MySQL. Otherwise, a float (double precision might be a good idea) should work.
Edit: It looks like the GeoRuby library includes a Rails extension for working with the spatial/GIS extensions for both of the aforementioned databases.