To use Ubuntu packages on your system, add one of the following lines
to your /etc/apt/sources.list or into a new file in your /etc/apt/sources.list.d/

For Trust Tahr

deb trusty/
deb-src trusty/

For Precise Pangolin

deb precise/
deb-src precise/

For Maverick Meerkat

deb maverick/
deb-src maverick/

For Karmic Koala

deb karmic/
deb-src karmic/

For Hardy Hardon

deb hardy/
deb-src hardy/

For Edgy Eft

deb edgy/
deb-src edgy/

For Dapper Drake

deb dapper/
deb-src dapper/

For Breezy Badger

deb breezy/
deb-src breezy/

I sign my packages.  To get my key, run this:

$ gpg --recv-key C5722326DA561D91
$ gpg -a --export C5722326DA561D91 | sudo apt-key add -

Blair Zajac