This one is a must! block annoying ads, avoid tracking cookies, and save your self some bandwidth (helps speed things up for everyone by not downloading ad images). This ad blocker also uses an anti-virus like subscription list which updates to avoid new ad servers all together. if it fails to block an ad. you can block it yourself; By frame, single image, or even the server (and supports wildcards like *).
Leetkey allows you to convert strings to other encoding and vice versa. binary, Hex, Base64, l33t, Rot13, Reverse, and even morse code. It also has a encryption module on it to encrypt and decrypt strings. Below are a few examples of these things encoded with leetkey.
Normal String: This is a test string
Reverse String: gnirts tset a si sihT
leet: 7h15 15 4 7357 57r1n6
Binary: 01010100 01101000 01101001 01110011 00100000 01101001 01110011 00100000 01100001 00100000 01110100 01100101 01110011 01110100 00100000 01110011 01110100 01110010 01101001 01101110 01100111
Hex: 54 68 69 73 20 69 73 20 61 20 74 65 73 74 20 73 74 72 69 6e 67
Rot13: Guvf vf n grfg fgevat
URL Encoding: This+is+a+test+string
Morse Code: - .... .. ... .. ... .- - . ... - ... - .-. .. -. --.
DES encrypted with password test: olZule+WVI7q4HtjQ90td/TiLFgBALW0GJmr0oMB958=
This shows you the IP address of server you are connected to in your status bar and always you to run whois, netcraft, Whoishostingthis.com, and ip2country. Good for security. If your at a wifi Hotspot and it shows your web-mail log-in page IP address is in the same LAN subnet, you are probably the victim of DNS Poisoning or a man-in-the-middle attack my friend. It might be worth your time to investigate the IP or move to a less hostile network.
FireBug and Firecookie
These two work together. Firebug can help you, in real time, debug a web page, highlights the code section on the page. also allows you to edit the code and then update it in real time (great for modifying web forms ;-] ). Firecookie allows you to look at your site cookie in real-time and edit and delete values in real time. All this is nicely done at the bottom of the browser! A MUST FOR WEB DEVELOPERS AND HACKERS ALIKE!
This tool allows you to right click and quickly craft advanced google searches based on the information on the web page using google operators like intitle: site: etc. Good tool for digging into a site using google ;-) if your unfamiliar with all this I suggest you read a book called "Google Hacking for penetration testers"