I don't know if anybody else is affected by #Microsoft killing #Skype, but I have a Skype number that I've used for like 15 years. I like it. A buddy of mine runs "TossableDigits" and they can port that number out of Skype. I get get SMSs on it, do call forwarding or voicemail, and even use an API to make changes to how it behaves.
The other common use case for this is for people that want to give out disposable numbers. You can get a number, use it a while, then throw it away.
All based in the US, and they don't make any super special guarantees about privacy. So I'm not sure it's great if you want throwaway numbers for dubious purposes. But women who don't want to give out their real number to men they just met is a good use case. Or maybe even an on-call rota so that the on-call number is always the same, but forwards to whomever is on-call. APIs would let you do that automatically.
Just thought I'd share. I don't get any commissions or anything.