Skype

Ubuntu 81.0 and later versions
Skype has provided a .deb package that can be found here. The deb for 8.10 has both 32 and 64bit version and has been tested on 8.10-9.10.

After you download the deb package double click on it to open and install it with GDebi.

Ubuntu 8.04
As of Skype version 2.1.0.81 there is no longer a package compatible with Ubuntu 8.04 Hardy Heron.