Some tools that I like and use frequently:

	find
	wget
	screen
	wc
	grep (and all the fun of regular expressions)
	awk
	sed

While not necessarily tools themselves, the following may also be interesting:

	Use of cron/crontabs
	Use of hosts.allow/deny to control access to network services

Or you could do some more advanced things with:

	find
	vi (and the fun things you can do with regular expressions there)
	bash scripting
	command pipelines


-- 

Steven Leikeim, GSEC-Gold        | We, the willing
Schulich School of Engineering   | led by the unknowing
Information Technologies         | are doing the impossible
                                 | for the ungrateful.
University of Calgary            | We have done so much
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                                 | we are now qualified
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