== Georeferencing ==
  Code works in UTM coordinates. Zone boundaries cannot be crossed: 
  Introduce nonstandard central meridians if necessary
  
  Could code be cast in terms of lat/lons?

  Make sure that georeferencing is used consistently (domain, pmesh, sww files, ...) (See ticket:16)  
  Test that least_squares (and elsewhere) correctly reconciles different georefs. (See Karratha) 

== Other ==
Ability to create additional quantities and initialise arbitrarily