Skype is proprietary. I don't think that it can be installed from the repos,
but I could be wrong. I don't use it. It is in my sources list, but my
sources are not standard.

You can install it from Ubuntu Tweak and you can install Ubuntu Tweak from
GetDeb.net
www.getdeb.net/updates/Ubuntu/10.10/?q=ubuntu+tweak

Ubuntu Tweak is a great utility that everyone should install. I also like
Ailurus which is th esame type of application, but different.

http://code.google.com/p/ailurus/

Both allow you to customise Ubuntu and install software. I don't know what
Backuppc is. You can install LuckyBackup or Back in Time from the repos and
both work well.