Old-styled notes in your extensions sidebar. http://fidel.im/classic-notes?en
Gmail on speed dial
Shows a preview of your unread mails on GMail
Bookmarks by the Side
A simple bookmarks sidebar.
I don't care about cookies
Remove cookie warnings from tens of thousands of 'infected' websites.
See real in-depth website engagement, traffic sources, and site ranking information with SimilarWeb extension.
Astronomy picture of the day
This extension shows the Astronomy Picture Of The Day in speeddial.
Print the current page you see.
Notifications on new emails, review topic of the email and sender, quick switch to reading emails.
Visual bookmarks, bookmarks sync across various browsers and absolute safety for your bookmarks
The missing bookmark manager for hte Opera Browser
Email Notifier is a notification extension that works with Gmail™, Yahoo! Mail, Live Mail, iCloud Mail, Mail.com and AOL Mail
Country Flag on Speed Dial
Shows your Country Flag and IP Address on Speed Dial
Instant Currency Rates
Get updates to the latest currency exchange rate in an Opera Speed Dial.
Advanced keyboard shortcuts fix
Fixes bugs that the 'Advanced keyboard shortcuts' feature has in Opera
Hi-res cover art grabber
Retrieves larger versions of cover art on various online stores, like App Store.
Rehost to Imgur
Upload images from web page to imgur.com using image context menu
Google Scholar Adder
Add a Google Scholar link to the Google search page.
LaTeX Editor and Compiler
Lookup things on Wikipedia
True Whois Lookup
1 click instant access, CAPTCHA free Whois lookup of any domain including ccTLD and new gTLD domains
Easy Tab Manager
Advance tab and Window management tool.
Share and Organize Like Never Before
Displays a binary clock in your speed dial.
uTorrent easy client
Extension add uTorrent web GUI in your web browser
Store, tag, search with your small notes.
Url in title
Appends the domain name of each tab to its title.
Shows the list of accesskey keyboard shortcuts of a webpage.
Calculator with multiple math functions that help people doing math easily.
DeskTime url fetcher
This extension allows desktime client to read current url.
Redirects GamerGate boycott websites to the archive.today versions.