There is a new phone service that offers auto expiring phone numbers. These will offer call forward to your current number for free. The intended use is to hide your current phone number.

Some services you get with this anonymous call forwarding number include:
1. ability to block calls from blocked numbers
2. the services automatically filters out known telemarketers calls.
3. Lets you enter a do not disturb time
4. Set a caller greeting

The only problem I see with this call forwarding service, iNumbr, is the fact that you don’t get your number rather a extension. Sure it’s free, but still, it feels cheap, and free like it is.

Free Anonymous Call Forwarding Phone Number, iNumbr
Sign up free via this link