Yes, but not in a very graceful fashion. The one I use on occasoion is ippi.com as a SIP provider. You can Google the proceedure to use the Skype/SIP gateway.
In a nutshell, the gateway is like dialing 9 on a PBX and outside callers needing to use an automated attendant to reach an extension, so you need to educate your Skype contacts on how to use it.
The cumbersome interface uses a Skype proxy for outgoing calls where the caller is ippi.com as the caller, and to call in from Skype, you add the poxy as a contact, then when connecting to the proxy, the caller is sent a text that needs to be replyed to with the "SIP extension" you are calling, so it does not support Skype directly. The caller needs two pieces of information to contact you, the Skype to ippi friend, then your sip user ID. For example if I used my slashdot handle, which I don't, my SIP address would be sip:firstname.lastname@example.org. The Skype caller would need to call the gateway Skype2ippi and then respond to the automated text and enter technician to ring my SIP phone.
Outgoing calls are simpler. I enter the full gateway/skype string into the speed dial settings on IPPI, so to call one of my friends, I just pick up the phone and speed dial them. IPPI speed dialer uses 2 digit speed dialing so you can save 99 contacts.
This works great with either a SIP softphone, or a hardware device such as an ATA and analog phone or an IP phone such as one of the Grandstream models.
The service does not provide video, only an audio connection.