oh no. that's a little bit of bad news (thanks for the answer though).
What i am trying to do is this: i'm getting longitude latitudes readings from a GPS and i'm trying to calculate distance between 2 given points (thus the distance between 2 points on a sphere).
I first convert my degrees in radians then apply the maths.
And it's a wearable so a computer is not an option.
Is the ATmega168 chip any better than the ATmega8 (... i don't suppose it would be better enough).