My fiance and I use Skype all the time, so much so that we just purchased a “phone” that hooks up to your modem so that you can use it around the house wireless-ly. Calls in (from landlines or cell phones, internationally or domestically) cost us nothing, and calls out cost cents a minute; I don’t find there to be a difference in quality between Skype-to-Skype “computer” calls and calls I make to landlines or cell phones.

We use it primarily to buffer the cost of international dialing. It probably saves us hundreds of dollars a month, and, oh yeah, it works. I know it just had that much-publicized downtime, but truly, we’ve used it for well over a year without a hitch.