To date, I haven't found Skype all that interesting. I mean, I have a cell phone with a bazillion-minute plan, unlimited long distance on my office phones and one-number service that forwards my calls to wherever I instruct it.
Why bother with Skype?
I've been listening to Adam Curry's Daily Source Code podcast and he's doing some interesting things in his new cottage studio using Skype with Audio Hijack Pro and outboard audio gear. Basically, the combination allows you to record phone interviews without a coupling device for a telephone.
In addition to all that podcasting goodness, a bluetooth headset actually makes Skype usable by removing the need to be tethered to a computer. (And sets me up nicely for my new Treo 650, with Bluetooth. Stay tuned...)