Get a VoIP phone. Connect it to your router or modem. Pay Switzernet 9 francs a month - you get a Swiss incoming number but can call quite a few countries for nothing (any many others for close to nothing).

Forwarding will cost you if you forward to your mobile. Why forward to fixnet? Dump it.

Siemens, for example, do some very friendly VoIP Gigaset models.

I've not had a landline for 5 years now.