On Ubuntu 10.04(Lucid Lynx LTS),Empathy IM Client is installed by default but if you are wondering whether the cross-platform voip application, Skype(a free voip software for making Internet call using voice over Internet protocol,audio call,video call and conference,instant messaging..) is available for Ubuntu 10.04 or not,then relax…It’s now available for Ubuntu or other Linux Distro.Skype 2.1 Beta 2 has just released for Ubuntu 10.04.Skype supports many flavors of Linux;In case of Ubuntu,it’s available for 32-bit ubuntu 10.04 as well as for 64-bit Ubuntu 10.04 LTS(Actually it supports only few latest version of ubuntu,after 8.10).
Download Skype for Ubuntu 10.04
Conclusion : Skype is a free-ware application not an open source!,if you want open source alternative to skype then install google talk or Empathy Client.