I found a great guide for Opera 9 which extends Opera tremendously. The guide is divided into seven sections: Menu editing, Integrating Opera with download managers, User Javascript, Buttons, Panels, Widgets and Misc. The menu editing section for instance has some great tips that enhance opera in great ways: It gives you tips how to integrate the bugmenot website into opera, it lets you lookup the bugmenot website for login information of the page you are visiting atm. You also find tips for the following things: How to open graphics with an image viewing program like irfanview, how to open websites with internet explorer or firefox, how to create tinyurls for the current url and much more.
The other sections are as helpful, I suggest you simply take a look at the whole article and see it for yourself. Implementation is really easy so you don“t have to worry a lot about difficult installation procedures.
Enjoyed the article?: Then sign-up for our free newsletter or RSS feed to kick off your day with the latest technology news and tips, or share the article with your friends and contacts on Facebook or Twitter.
Related Articles:
Opera add-onsFirefox Tweak Guide
Opera 10.50 Alpha Released [Opera]
Windows Vista Performance and Tuning Guide
Opera Software Readies Opera 11.51 Maintenance Release

That’s sounds interesting. I’ll give it a try, but, being a Opera user around four or five years, problably doens’t have much things that I don’t know.
(Except for how to spell properly :)