Absolutely - I'm currently trying to pay equal to my normal mortgage payments as an overpayment.
The reason being is simple - I have the cash now, but running my own business means a lot of uncertainty, so at least if my business were to go belly-up, at least I should hopefully have paid off a reasonable chunk from my mortgage.
Although I originally signed up for a 30 year mortgage, to allow for lower payments and therefore more room in case of trouble, if I were to continue my overpayments at the current rate, I could have my mortgage paid off in 8 years. Doing so would save me around £100k+ on interest repayments.
I made sure I was fine to make overpayments before taking out my mortgage, and so far so good.