Google latitude now gives you the option of enabling ‘history’ – you can enable it here.
It’s kind of neat, and I can see it being somewhat fun to use if you go on long trips. I gave it a little test run while I was on the train back to Toronto the other day – and although I was only using my iPod Touch with WiFi tracking, it was pretty decent as far as being able to keep me pin-pointed as to where I was.
And yes, you get the option to delete parts – or all of your history. (the lack of tracking between brantford and burlington is due to the lack of wifi in the open country side).