Call with another caller ID

Dear Android enthusiasts, I have a landline telephone with expensive calling rates, while the contract in my android smartphone is quite cheap. In order to save money I would like to call with my handy, but showing the telephone number **of my landline**. In that way people can call me back and I avoid revealing my smartphone number. Do you have any idea, how to show another telephone number when calling? I know how to hide the number, but that is no solution. Thanks!