chdist, for easily working on packages from multiple distributions
If you ever need to do backports, I recommend the chdist tool. While working on one.ubuntu.com, I have frequently found myself needing to try out packages on both Ubuntu 8.04 and Ubuntu 9.10 (currently under development), often backporting a package from Karmic to Hardy. I've been running 9.10 (Karmic) on my primary laptop since the first alpha in order to work on packages included in the desktop, but we also need to run many of those same packages (Erlang, CouchDB, python-desktopcouch) on our server farms in the data center. Last week Tom Haddon showed me chdist, which makes it considerably simpler to work on backports, especially grabbing sourcepackages from an older distro version. http://packages.ubuntu.com is always nice for checking which version of a package is in the last few versions of Ubuntu, but chdist is even handier, since you can build APT trees for several different releases on the same machine, without requiring much disk space. Now I just need to finally learn how to use kvm, and I'll be able to test the backports as well as make them.