Lets face this sittuation when you have a large no of zips or rar files or tar files in a directory. You want to unzip all of them in one go…
For unzipping multiple zip files in a directory use this command (first change to that directory).
$unzip ‘*.zip’
those quotes are necessary.. it prevents the shell from expanding the wild characters..
Now if you want to untar large no of files use
$tar -xvf ‘*.tar’
Each File and directory on you hardisk counts 1 inode. Now if you are using a webhost if you need to find no of files occupying you hosting account here is the code. This works only if you have shell access.
find . -printf “%i\n” | sort -u | wc -l
you can also use the following instead of above
find * -print | wc -l
To install extension in openoffice first go to (click on image below to go to site) Extension Section of Open Office Website.
Download the extension you want by searching on that website and copy it to any folder which you will not be deleting.
No open any one of the openoffice.org applications.
Go to Tools—> Extension Manager as shown in figure
Now click on add in the extension manager window.
Now select the downloaded extension file and click on open.
Now you can see you extension installed. Check for versions for which the extensions are valid before downloading
Steps for cropping or cutting parts of image using gimp in Linux
1) Open the image in gimp
2) Select the cropping button as shown in figure 
or go to tools–>transform tools –> crop
3) Select the area of the image you want to crop
4) Click Inside the selected area and you will see the crop image and save it.
These are the text webbrowsers in linux. That means you can search web or surf the net using these. You can also view html from console using these text browsers. Here is the list
w3m
This is one of the simplest internet browsers you have seen..
Then we have links. This is sibling of w3m
Elinks. IT is a bit more complicated that links & w3m and has commanline user interface.
Lynx
This webbrowser is suggested by google to simulate web spider.
Use GIMP to scale images in linux. Gimp is user friendly and very easy to use.
Scaling or resizing images in gimp is an easy task.
1) Open the image in gimp
2) Click on the scale button and click on image 
or go to Image –> Scale as shown in figure
You will see the options as below. Now change the size you want to scale the original image and click on save button. Now save the image.
Ok if you want to add transparent background to your picture or png files in linux these are the steps you need to follow
1) First Open the image with GIMP
2) Go to layer-> Transparency -> Add Alpha Channel
3) Now click on the fuzzy selector tool and click on the area of the image which you want to make transparent.
4)Now go to Edit –> clear as shown in figure
5) Now you can see the final image after making the background transparent.
Cheers,
Have fun with gimp
If you open unix text files in windows there are strange characters appearing instead of text. The same happens if you open dos text files in unix you will see strange characters like ^M at the end of each line. you can use dos2unix program to convert these dos files into unix text file format.
usage
$dos2unix file.txt
converts file.txt from Dos format to unix format and replaces it. You can also use fromdos to same the thing
$fromdos file.txt
There is another command unix2dos to reverse the task
$unix2dos file.txt
converts file.txt from unix format to dos format and replaces it… you can use todos to do the same task as
$todos file.txt
Chm files are Microsoft help files. They can be viewed or opened in linux using Gnochm, Kchm, Kchmviewer and Xchm.
Gnochm is used in Gnome desktop environment (you can use this in KDE but its recommended to use Kchm or kchmviewer). Kchm and Kchmviewer are KDE desktop applications and they can be used to view .CHM Files in KDE. Xchm is a xwindow application with minimal graphical interface. It looks outdated but works fine.
to open a file you have to type it like
$xchm filename.chm
just replace xchm with gnochm or kchm if you want to open file with them.
Update:
One of the Reader “kounryusui” mentioned that there is a extension available in firefox with which you can open chm files. Here is link for extension of firefox to open chm files.
Here are the screen shots of each of above applications
XCHM
GNOCHM
KCHM
KCHMVIEWER
To receive and send emails from evolution by your Gmail account you need to enable pop3 forwarding. To enable it you need to go to setting–> Forwarding and PoP/IMAP in your gmail settings.
Now select the option
and save the settings.
Start the evolution mail client then you will face this dialog if no email accounts are configured. If you have already email accounts configured in evolution then goto tool –> preferences–> mail accounts or edit–> preferences–>mail accounts and click on add button to add new email account.
Click on forward and you will see a window asking for you name and email address.
Type your Name and email address including @gmail.com as show below in the figures.
Optionally if you want to make your gmail account default then check the option make this my default account and click forward.
Now you have to configure the incoming server settings.
Select Server Type as POP/POP3 enter
in field server : – pop.gmail.com
in field Username:- yourmailid@gmail.com
Type of secure connection as SSL
and authenication Password
and click forward to go to next screen.
Set the frequency with which evolution checks for new mails like from 10 minutes to 5minutes etc. Now check the option Leave messages on server so that the all messages are still on the server and not deleted once downloaded in your computer.
You can to configure your outgoing server so that you can send emails
Select the Server Type as SMTP
enter the server address as smtp.gmail.com
click on server requires authentication and type of authentication as plain and enter your username yourmailid@gmail.com
also Use Secure Connecion : SSL Encryption
click forward to goto next screen.
Give a Name for you account in evolution like GMAIL account of My Gmail Account. This is different name which will be useful when changing the email addresses for that account.
Select you timezone in the next screen
That all click forward and finish and you will be all set with evolution mail client ready to use with your gmail account.