Thought I'd share some interesting web sites with you.

This is a good one for walkers and runners - a Google map mashup that let's you click a route onto the map and it calculates how far the distance is. Very useful, especially with a 10K run on the horizon it let's you accurately chart your training miles.
Pedometer

The next one is a bit funny - it's built into Google Earth and is a flight sim.
Flight sim
I was useless and kept crashing...