If you have more than one Skype account – say one for business and another for personal use – you can run two Skype applications at the same time! Provided you have Skype version 4 or better. The following “tip” applies only to Windows…
Step 1: Go to the location to where you installed Skype. For example:
C:\Program Files\Skype\Phone
Step 2: Right-click on the Skype.exe icon and select “Send to” -> “Desktop (as shortcut)” to create a new shortcut to it on your Desktop.
Step 3: Now go to your Desktop and right-click on the newly created shortcut. Select “Properties”.
Step 4: Append the following to the “Target:” text field without changing the existing text:
/secondary
Enjoy