adx is a minimalistic but massively Web-enabled address book that runs completely in your Web browser. It's OS-independent and supports comprehensive details for each contact entry, including user identifiers and profiles for Skype, Twitter, Flickr, Delicious, Facebook, LinkedIn, studiVZ, instant messengers, etc. It supports the hCard and XFN microformats.
iMacros for Chrome is an extension that allows you to automate repetitive tasks like visiting the same sites every day, filling out forms, and remembering passwords. It can automatically fill Web forms that stretch over several pages. It can automate the download and upload of images, files, or entire pages (with or without images). iMacros includes a user agent switcher, functions to download PDF and Flash, and ad-blocking and image-blocking functions. iMacros can automatically read data from a Web site and export it to CSV files. You can use this feature to download stock quotes, gather and compare Web store prices, and more. Web professionals can use iMacros for functional, performance, and regression testing of Web applications.
Aletheia is a browser-like application for sending raw HTTP requests. It is designed for debugging and finding security issues in Web applications. It is possible to apply filters on every request and response which can modify the content, for making Basic Authentication or OAuth requests, for example. Because it is possible to modify every bit of the request, it is easy to exploit Web applications. That means you can set, for example, custom Cookies or User-Agents, or send file uploads to the server. It uses the Apache HTTP core components library to send HTTP requests. This application also helps you understand how the HTTP protocol works.