1CC has the ability to dial Skype usernames. For instance, 899099johnsmith will dial the phone of the person with Skype name of johnsmith on the Skype phone network. The network number 099 is the key to tell Net2Max to route over the Skype network. In fact, Net2Max can route to other VoIP networks. Check out the Net2MAX web dialer list here which mentions the Skype prefix 099 as well as 098 for SIP IP Address, 092 - MSN Live Messenger, 091 - Google Talk, 093 - Yahoo Messenger, and more.
Scopezoom explains in the last part of the tutorial:
If it worked, it means all calls directed to *7749Your1CCNumber@sipbroker.com or Your1CCNumber@sip.syd.net2max.com will ring your Skype.
Now all you have to do to assign a SkypeIn number is forward any DID number you have to that URI... (Services like MySipSwitch.com, PBXes.com or VoXalot.com can help you forward to a SIP URI if your current provider does not offer this feature)
With your SIP DID you can forward it to a SIP URI. This SIP URI then forwards the call to your Skype username. Then when you can call the SIP DID it will route the call to the Skype username.
So what's the point other than SIP to Skype username calling? Well, you can use PontiVoce (which I wrote about here) to control your Skype client to do some cool stuff. Essentially, PontiVoce lets you turn your PC into a Skype gateway, allowing you to dial into your PC running Skype and then initiate an outbound call at SkypeOut rates. Thus, using this tutorial you can make a SIP URI call to Skype (free), have PontiVoce answer the call, then initiate an outbound call using SkypeOut credits. If you have SkypeUnlimited (U.S. and Canada) then the call is 100% free. Or if you have a SIP desktop phone that allows SIP URL dialing, you can call your Skype buddy using your high-quality SIP desktop phone - perhaps even using a headset. I'm sure there are other cool applications as well.