Unrar

Launch Synaptic Package Manager, search for unrar. You will get two available unarchiver unrar and unrar-free. Unrar-free come out with limited function compare with unrar (non-free version). It's up to you which unrar you want to install.

For me, I choose unrar (non-free version). Mark it for installation. Once completed, you will be able to view/unrar .rar file extension.

Install unrar using terminal;
root@support-t60:~# apt-get install unrar

mtr

mtr (Matt's Traceroute) combines the functionality of the traceroute and ping programs in a single network diagnostic tool. This tool is very useful to traceroute IP or host because you can get better result (if using normal traceroute, the result sometimes has been filtered out by ISP router).

There are two version of mtr, mtr-tiny and mtr. The different is mtr-tiny run and display its output in terminal while mtr display output in its own window.

To install mtr you can use apt-get;

1. apt-get install mtr
2. apt-get install mtr-tiny

Below is terminal output when I installed mtr on my laptop;

root@support-t60:~# apt-get install mtr
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be REMOVED:
mtr-tiny
The following NEW packages will be installed:
mtr
0 upgraded, 1 newly installed, 1 to remove and 0 not upgraded.
Need to get 49.0kB of archives.
After this operation, 61.4kB of additional disk space will be used.
Do you want to continue [Y/n]? y
Get:1 http://my.archive.ubuntu.com hardy/universe mtr 0.72-2ubuntu1 [49.0kB]
Fetched 49.0kB in 2s (19.7kB/s)
(Reading database ... 99002 files and directories currently installed.)
Removing mtr-tiny ...
Selecting previously deselected package mtr.
(Reading database ... 98997 files and directories currently installed.)
Unpacking mtr (from .../mtr_0.72-2ubuntu1_i386.deb) ...
Setting up mtr (0.72-2ubuntu1) ...

root@support-t60:~#