My 2c

Useful Linux tools

1. units
units is a command line application, which converts units from one scale to another, e.g. covert x ms to years, …
Small & simple, yet very powerful and easy to use.

2. SSH config & bash completion
One thing I was missing from putty under Windows was the “saved session” feature, which allows to connect to a remote system with the saved connection details.
You can make things easier under Linux via the ssh config and bash completion.
Depending on your Linux distribution you may have to install bash completion first, see here for details: http://freshmeat.net/projects/bashcompletion/

After installing bash completion edit your

~/.ssh/config

file and add the following lines:

Host server.name
HostName IP

where “server.name” needs to be replaced with the server name and “IP” with the server IP, e.g.:

Host server1.myserver.com
HostName 111.111.111.111

Afterwards you will be able to enter

ssh se

and hit the TAB key for auto completion to

ssh server1.myserver.com

the same goes for the IP as well.
This is extremely usefull when you are dealing with a great number of servers and especially when you are connecting via OpenSSH public key authentication.

3. vim
I am going to write about vim in more detail later on, but just to add to the list of useful tools.
Properly configured it can hold its own even when compared to the big GUI editors.
Make that “especially” when compared to the big GUI editors, if you’re a fast typer and learned vim’s shortcuts.
I have been using it for my latest CakePHP project and will provide some more details later on.