My office looks out over Toolonlahti (any Finns reading - I know both the "o"s and "a" in the name should have dots over them, but blogspot doesn't seem to take Finnish letters), a lake in the centre of Helsinki which is just linked to the sea about 500 mtrs away. This being Finland and winter - it is well frozen. Right now, in the centre of this flat whiteness the size of maybe 5 or 6 football pitches, there are two people doing tai-chi.

They look very very silly.