I found MapMyRide today, via Lifehacker - it lets you map bike rides or running routes. I added my weekly run - you can see it here:
[edit: it appears not to be working. Rubbishness! Try this link instead.]
Actually I'm not really doing any running at all at the moment, for reasons I won't go into here. Hopefully that'll change next month though. I feel like I've not done anything strenuous for ages and ages.