BTW, for anyone who wants to experiment with adding a wide variety of .deb repositories (that is, for anyone who makes assiduous backups):

https://sites.google.com/site/mydebiansourceslist/Home

I remember trading info on obscure .deb repos with Craig years before he started this page. Now I find he has certainly the most informative single resource for .debs on the net. Also, I am certain Craig would be interested to here of more repos. (Knoppix is on there.)