How much to tip a taxi?

[urban1]

Did you guys know that in Calgary its against the Taxi commission rules for a cab driver to use a cell-phone without the consent of all the passengers in the cab?

I get this one cab driver often - hes young and is always yapping on his cellphone and has a tv/dvd in the cab on which he plays foreign music videos.

[mykalberta]

For me it would depend on the service. I always keep my eye on the spedometer to make sure he is keeping up with things. If he is an I fealt he tried to get me to my destination faster than another cabbie would have a tip is warranted - normally 25-50% - most becuase I only use one cab company and I have seen the same drivers often enough.