DELETE n1 FROM table n1, table n2 WHERE n1.id > 10000 AND n1.id < 11000 AND n1.id > n2.id AND n1.EMAIL = n2.EMAIL;

The above MySQL query will delete duplicate email addresses between the id’s 10000 and 11000. Breaking the query into blocks of 1000 id’s will reduce strain the MySQL server.

select EMAIL, count(EMAIL) as cnt
from TABLE
group by EMAIL
having cnt > 1 ORDER BY `cnt` DESC

The above MySQL query will find and list the number of multiple duplicate emails in a table.

http://www.tineye.com/ allows you to search the web for similar images to ones uploaded or on the web.

UPDATE: Google has this as well: http://www.google.com/insidesearch/searchbyimage.html

• www.qrstuff.com ? You can generate QR Codes (the most popular 2D barcode) for Website URL, YouTube Video, Google Maps Location, Social Media, iTunes Link, Plain Text, Telephone Number, SMS Message, Email Address, Email Message, Contact Details (VCARD), Event (VCALENDAR), Wifi Login (Android Only), Paypal Buy Now Link. With QRstuff.com you to change colour of the positive QR Code shapes (the dark part).
• qrcode.littleidiot.be ? You can generate QR Codes for Regular text, Hyperlink, Phone number, Email address, meCard, vCard, WiFi settings. There is also the option to download the QR Code in multiple formats, particularly vector based formats. QR Stuff only does raster (bitmap) formats.

• http://eclecticdjs.com/mike/tutorials/php/imagemagick/
• http://jamesroberts.name/blog/tag/imagick/
• Mikko’s blog

imagick is a more advanced graphics library than the default GD for PHP, but the ImageMagick PHP library imagick is only documented on PHP.net comments, so using the library can be a bit challenging, but the sites above help in using the library.