There are some basic packages that the basic distro of Ubuntu Server (as of 'Feisty' 7.04) does not include. I was just documenting a bit the sequence of apt-get commands I used right after the install was done:

apt-get update
apt-get upgrade
apt-get install ssh
apt-get install lynx
apt-get install links
apt-get install vim
apt-get install gcc
apt-get install make
apt-get install sun-java6-bin
apt-get install sun-java6-jdk
apt-get install subversion
apt-get install smbclient
apt-get install smbfs

The update and upgrade commands are to update apt-get's lists and then upgrade packages that were just installed from CD, respectively.

Some of these are perhaps a bit less common -- smbfs maybe. But vim? gcc? make? Really? Not to mention ssh. The client of SSH comes in pre-installed, but you have to install the server.

I imagine there's some weird reason that has to do with copyrights or encryption, or the copyrights of encryption, but it's still a pain. Especially if you forget about doing it...