Skype is being used by millions of people, and not all of them are casual users. Heavy users or small business owners should check out Pamela Professonal ($40, 30-day free trial), a software app that adds a lot of useful tools to the Skype experience.

One of the best features Pamela offers is the ability to record phone calls, both audio and video. This is great if you run a company that relies on verbal agreements, or if you simply want to keep a call archive.

You can decide in the options whether or not the other person in the call should be told that the call is being recorded. But if you turn it off, bear in mind that you may be breaking local laws. Once the call is finished, you can arrange for the media file to be immediately emailed to you.

Another cool feature is the ability for all chat messages to receive a standard pre-written auto-reply message. This is good for when you are not at your desk but you want the other person to receive some kind of a response (such as your current contact phone number).

You can also set up auto-responder messages to be sent to Skype users who try to call you when you are on another call, telling them to try again later when you've finished with your current call. If you're running a business, little touches like this can be deeply appreciated by a customer.

Call scheduling is also worth mentioning.

You can set up calls that you want to make to another Skype user or to a SkypeOut number. You can specify a subject for the call and whether or not you want an alert a certain number of minutes before the call is due to start. The call can be scheduled as "recurring" so if you have a call which you make often, then you don't have to keep inputting the same details over and over.

Voicemail is another area that Pamela does really well. You can set up your own custom voicemail messages, set up an auto-responder Skype chat message telling the caller they are being redirected to voicemail, set up an auto-responder Skype chat message after the voicemail has been left, telling the caller that they successfully left the message, and more. If you are using Pamela Pro for your small business, you can even specify what times the voicemail should switch on and off.

The remaining two features, PamCasting and Blogging, are to help you get your media files out to the wider world, if you are into podcasting and blogging.

Pamela Professional is not cheap. Anything labeled "professional" rarely is. But if you use Skype heavily every day, you should consider getting Pamela Professional. It's one app that picks up where Skype falls short.