here's one i recenly found :

tab completion {BASH} :
if you have a long file name that you don't wanna type you can type a few letters then tab. * works dometimes too.

Tab completion is good, I wasn't aware of this up untill Spring 1999, really, I had no clue there was such a thing. In csh/tcsh you can use Esc key twice to simulate the same effect though, on most UNIX's you don't have that beauty that Linux user-friendlyness offers like when you press a tab key you have a list what's avalalble, guess what zsh went further, you can write your own functions for completion, and when you press for instance
ssh [TAB]
it will give you the list of recent hosts you've connected to and it will give you all the available command line switches for ssh command , beautiful? Bash development didn't sleep all that time, and now you can have the same behavior with bash check out http://www.caliban.org/bash/index.shtml#completion
and A couple of oldies from me:
!$ - holds the last command line argument, example
ls -d superduperdirectory*
superduperdirectory1 superduperdirectory2 superduperdirectory.3
mkdir superduperdirectory43
cd !$
and you are in superduperdirectory43

Another tip: argument sugsitiution, for instance your boss told you to print 5 documents to his printer and he'd call you when to print the next document, you know he/she wants to look throught them to verify some data in reality he/she just want to show you who's the boss
the docs names are reather long but they have a common part

superduperdocumentaboutbossfamily
superduperdocaboutbosscreditcards
superduperdocaboutbossschedule

so you are in command line
and you could just issue one command
lp -dsuperduperprinter superdup*
and be happy, but instead your boss was anal enough to ask you delay every doc, here's the solution, it might be not that preaty but it saves typeing command parts espacially when you are at CLI w/o gpm running (no easy copy/paste)
lp -dsuperduperprinter superduperdocumentaboutbossfamily
boss calls for the next doc
^umentaboutbossfamily^aboutbosscreditcards
boss gets his next report, three minutes later he shouts to print the third cocument
^creditcards^schedule
So as you see whatever placed between ^ (carot symbol) is replaced by whatever follows.
Good day everyone, it is time to go to work

Here is another one, have you ever been stumpped by a corrupted tarred backup and you are so desperately needing this particular file from this particular backup?

EXTRACT CORRUPTED TAR FILE

In many case if there is a corrupted tar file,
the following command can be used in an attempt
to extract the file:

% cat [tar-filename] | tar -xvf -

NOTE: Where "-" is the STDOUT
It might work with tar.gz as well just include z flag in the tar command.
This tip generously provided by http://www.ugu.com

Press Tab 2 or 3 times at a bash prompt and you will get a list of all available commands.

We're all more/less familiar with pagers like more and less Some prefer view the files with
more filename
less filename
What if you saw something you want to change while paging trough the file?
Some might think:"Oh, well, I'll quit more and edit the file with text editor..."
But there is a way to invoke vi from within more/less pager, just view the file with more/less as you normaly would do, and when you decide to change something press v to go into "vi mode". Edit, save, quit vi and you back in more/less.

Dude! That one is sweet, well I guess it's time to learn more vi... Damn vi! Why can't it be more like pico, all user friendly and crap

Just kidding, really. That's an awesome trick, thanks!

Cool

Another trick that I've forgotten about but kind ppl over UGU have refreshed my memory on:
Generally, it is no good to have root shell hanging in the air while you're concetrating on your own account, but I myself use it all the time while oing system maintenance.

Here's one more tip

Here's another one: if you aliases a lot you can use Bash' "unalias" builtin or you can precede the command with a backslash. Stupid example: if you have something like "alias ps='ps ax -eo user,pid,priority,args'", then use \ps will do the trick.

I'm trying like mad to free up some space on my drive, and I happen to remember you posting this from this thread However, I get an error:
And that's it. I am not sure why, but I've got a sneaking suspicion it's something to do with xargs Anyway, can someone enlighten me? Thank you! Also, I would like for this to go into all subdirectories if that's possible?

Thanks again

I am not sure why it isn't working for you it does the trick for me, and it does go further into subdirectories, try to encase du -sm into quotes it might be it, but again it works fine for me on my slack install.

Sorry Boris, but it's a no go... I just tried as root too just to make sure it's not some odd permissions thing.

Hmmm, I'll see what I can find.

Thanks for the suggestion though

Wow, what a cool thread. Thanks to whoever dug this one up...

Anyway, my little trick: All the gurus will know this one but it might be useful for the n00bs. In your .bashrc add:
and you don't have to type those annoying flags to get different list results. Of course you can do this with any command you fancy.

No.
executes make install regardless of the exit status of make. So, if
make failed (non zero exit status), make install would still be
executed. bad.

&& can be thought of as an "AND" operator (well, it IS an AND
operator), so the first has to be true for the second to be
executed, make needs to have an exit status of 0.

will execute ./configure if and only if make exits with a non zero
status (fails). This is the logical OR operator.

(man bash, and you'll get this information, it's probably also in
all the other shells' man pages)

why not just this:

make dep ; make clean ; make bzImage ; make modules ; make modules_install

and sorry MC we can't make fun of those guys and their euro until we stop measuring the trip to the bank in miles