I have been using debian for ages, but I still don't know all the tricks or how to use all the advanced apt / dpkg features, and I didn't need to with debian. But because knoppix has a somewhat difficult package selection, having a list of the common commands could be handy to answer questions on this forum.

I'm talking about stuff like how to "hold back" a package, how to install one from a particular release etc.

So here goes, help me out here.. Hope this can be come a quick reference.

To list all the files in a package
dpkg -L packagename
to install a package of a particular release ( assuming it's in your sources.list )
apt-get install -t unstable packagename