I find these tools really make life easier.
mlocate
mlocate is a nice file search tool. Better than slocate because it respects permissions when searching. Faster and easier to use then find because it uses a database. As of Ubuntu 9.0.4 is part of the installation and it looks like a cron is already setup to keep the search index database up to date.
sudo apt-get install mlocate sudo updatedb # If you want to manually update the database.
ne Editor
ne is an editor similar to DOS Edit. It is menu driven and easy to use for new people. The only thing I wish it had was to be able to select text with the shift and arrow keys like DOS Edit.
sudo apt-get install ne # Nice easy to use editor like DOS edit
htop
Great tool to view system performance and what is happening to various processes.
sudo apt-get install htop
Others
Here are a bunch of more useful tools we recommend having,
sudo apt-get install screen # persist sessions across network disconnects, share terminal shell sessions (both can type at once) with others sudo apt-get install colordiff wdiff # diff tools to colourize diff files and word diff to diff at a word level (rather then the regular line) sudo apt-get install telnet # great for verifying connection to listening ports
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