Is it possible to hide your IP address from all and sundry?
Any firewalls / programs that can do it. Free?
it depends on what exactly you are looking to achieve
Privacy.
Just sick of everyone knowing your IP address etc.
Just sick of everyone knowing your IP address etc.
Whichever way you choose (proxy/tor) you will be passing all of your traffic through another computer so you're potentially giving away some of your privacy, so be sure you can trust whichever company/organisation you use.
As said ^^, tor is pretty much the most anonymous and is free.