  Some nifty but obscure (obscure to relative Unix newbies like me anyway) things come along with the BSD layer. For instance there's the "look" command, which by default searches /usr/share/dict/words (a list of about 250,000 English words and proper names).
You can't use regular expressions with "look", though. For more flexibility (let's say you're a word-game nut), define this alias: alias words cat /usr/share/dict/words | egrep To mimic the behavior of look foo you'd type words -i ^foo , but now you can do many more cool and useless things (like finding all words in which the letters "abcde" appear in sequence: words "a.*b.*c.*d. *e" ). You'll be completing impossible rhyming couplets faster than you can say "zygosporange.
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