I’ve been playing with VOIP products a lot recently. For instance, I learned you can make VOIP calls through Gizmo5 [registration currently closed] using your Google Voice number. That’s pretty handy when you’re in another country – so long as you’ve got wifi, you’ve got a US phone number. For free. Since Google purchased Gizmo5, I expect we’ll see some interesting offerings when the product is re-launched.
But I digress. As great as the above combo is, I still often connect with others using Skype. This lead me to start collecting their IDs on the contact record. From there it is pretty simple to create a URL to dial them through Skype directly.
Skype ID is a text field. Skype URL is a formula field using the following:
IF( LEN(Skype_ID__c) > 0, HYPERLINK("skype:" & Skype_ID__c & "?call", "Skype " & Skype_ID__c ), "No Skype ID")
This can also be implemented as a button using this code:
skype:{!Contact.Skype_ID__c}?call
Happy dialing. Cheers,
John

I must have had the Skype FF plugin disabled, as this should not normally be needed. Skype can automatically match the name of the person to their Skype ID.
Although this could still be useful those using Chrome or other browsers where the plugin is not present.