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Geolocate a given IP address
GeoIP Needs to be installed. Can be done from some distro's or via MaxMind.com for free. There even is a free city database availabble. If the GeoLiteCity is downloaded and installed it will also find more information $ geoiplookup -f /var/lib/GeoIP/GeoLiteCity.dat commandlinefu.com GeoIP City Edition, Rev 1: US, NJ, Absecon, 08201, 39.420898, -74.497704, 504, 609

Reverse SSHfs mount,
While `sshfs $REMOTE_HOST:$REMOTE_PATH $LOCAL_PATH` "pulls" a directory from the remote server to the local host, the above command does the reverse and "pushes" a directory from the local host to the remote server. This makes use of the "slave" option of sshfs which instructs it to communicate over plain stdin/stdout and the `dpipe` tool from vde2 to connect the sftp-server stdout to the sshfs stdin and vice-versa.

Tell Analytics to fuck itself.
See http://code.google.com/apis/analytics/docs/concepts/gaConceptsCookies.html if you are unclear about the Google Analytics cookie system. If Firefox is your daily browser, be a good Orwellian and run this command regularly. If you see, 'SQL error near line 1: database is locked', close Firefox and run again.

List open IPv4 connections

Schedule Nice Background Commands That Won't Die on Logout - Alternative to nohup and at
Check out the usage of 'trap', you may not have seen this one much. This command provides a way to schedule commands at certain times by running them after sleep finishes sleeping. In the example 'sleep 2h' sleeps for 2 hours. What is cool about this command is that it uses the 'trap' builtin bash command to remove the SIGHUP trap that normally exits all processes started by the shell upon logout. The 'trap 1' command then restores the normal SIGHUP behaviour. It also uses the 'nice -n 19' command which causes the sleep process to be run with minimal CPU. Further, it runs all the commands within the 2nd parentheses in the background. This is sweet cuz you can fire off as many of these as you want. Very helpful for shell scripts.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Relocate a file or directory, but keep it accessible on the old location throug a simlink.
Used for moving stuff around on a fileserver

Instant mirror from your laptop + webcam (fullscreen+grab)
This directly puts the "mirror" into fullscreen, and lets you take photos by pressing the 's' key. I bet appearance conscious people will have keyboard shortcut for this command by now.

Monitor ElasticSearch cluster health - Useful for keeping an eye on ES when rebalancing takes place


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