I was getting tired of paying Vonage $35 / month (after taxes) for a phone line. Plus I found I liked using Skype for making calls because I could do it hands free. I also have a Google Voice number I give out because it rings my office (Vonage) and mobile.
What to do?
For $3.00 / month you get unlimited calls on Skype, plus you can call from your iPad or laptop. I set the caller id to my Google voice number. Google Voice is free this year in the US, so I use that to make traditional handset calls (ringing my analogue Vonage phone). I cut Vonage down to 300 minutes for $17/month (after taxes). I'm now $14 / month ahead and have a very flexible phone system.