I love Opera, I really do. It’s an awesome web browser, and it’s a shame that it doesn’t have more market share (most stats put it around 1% or less). I could go on for days about the many different reasons that Opera rocks, but here are my favorite ten (in no particular order, based on the latest version, 9.1):
Paste and go (Screenshot)
This one really shows the attention to detail that the Opera team has. How many times have you copied a URL to the clipboard, only to go paste it in the address bar of your browser? Then you have to click go or press enter. With this handy feature, Opera saves you that second step. As the name suggests, you can paste and go all in one step!
Instant back and forward
I don’t think this is listed as an official feature, but it should be! In IE or Firefox, clicking back will usually take a few seconds for the previous page to reload – not so in Opera. As soon as you press back (or forward) the previous (or next) page is instantly there. Firefox is pretty good at this too, but Opera is quite simply superior.
Highlighted Text Context Menu (Screenshot)
As soon as you highlight some text in Opera, a context menu appears with a bunch of useful commands at the ready. Again, it saves that extra step of right clicking after you have highlighted text. It might sound inconsequential, but it makes a huge difference.
Top 10 Sites (Screenshot)
Everyone has a set of websites they regularly visit. Opera is smart enough to keep track of these sites, and gives the ten most visited sites a special and easy-to-access menu. It’s kind of like automatic favorites. Very handy.
Notes
After experiencing this feature, you’ll wonder how you ever got by without it. Ever keep notepad open while browsing so you can copy things you might need later? No need to do so with Opera! Highlight any text and you can then turn it into a note, or you can manually create a note with whatever text you want. Notes are associated with a website too, so you can quickly see your notes for a given page. Incredibly useful feature.
Better Tabbed Browsing
All modern browsers have tabbed browsing, but none of them do it as well as Opera does. For one thing, tabs are ordered (say you have three tabs, A, B, C. Click on A, then click on C, then close C. Opera goes back to A, the other browsers go to B). Again with the attention to detail, right click on any link and you have two options: open in a new tab (which brings it to the front) or open in a new background tab (which does not). Awesome.
Search Keywords & Create Search (Screenshot)
IE and Firefox handle search engines pretty well (with the search box I mean), but it’s pretty much up to the site developer to help the browsers recognize the search engine. Not so in Opera. Right click in any search box and choose “Create search…” and automagically you have a new entry in your search engines. You can also associate keywords with engines. So for dictionary.com, you might associate “d”. Then you can type “d word” in the address bar, and Opera will take you there.
Mouse Gestures
Of all my favorite features, this one takes the most getting used to. Essentially mouse gestures allow you to navigate or modify the window using only the mouse. Just another small feature that can save you a bunch of time.
Trash Can
Have you ever closed a tab, only to realize a few moments later that you still need it? In other browsers you have to try to get back to the page again. In Opera, just click on the Trash Can, and choose the tab you closed. So damn handy.
Site Preferences
This feature gives you the ability to modify preferences only for a given site. Want to turn off javascript just for one site? Opera lets you do it. Not a feature you’ll use daily, but it can definitely come in handy.
Like I said, I could go on! If you like what you see, you should definitely try Opera. It’s completely free, and there are no advertisements inside (much older versions had a banner). And if you’re afraid your favorite sites won’t load correctly, don’t worry. It’s increasingly rare to find a site that doesn’t work correctly in Opera. And actually, Opera is the only Acid2-compliant browser for Windows!
In fact, I have just one problem with Opera – my del.icio.us page loads incredibly slowly. I have no idea why, but I’d like to get it fixed. If you have any ideas, let me know!
UPDATE: It appears Opera simply doesn’t like my huge list of tags. I changed my del.icio.us preferences to display as a cloud, and only tags with at least 5 items, and now it loads very quickly!
Read: Opera
MasterMaq's Blog 
I was going to give you a hard time about how these fringe browsers are our nemisis as web 2.0 guys….but you have made a very compelling argument here, and I am going to give it a try.
"open in a new tab (which brings it to the front) or open in a new background tab (which does not)" IE 7 does this with CTRL and CTRL+SHIFT. I’m not sure if you were saying these are exclusive features.
What I’d like is CTRL+N in a tab. CTRL+N in IE opens another window with the history maintained. I’d like that in a tab.
I’d also like to be able to move where a page is shown by dragging tabs between IE instances.
I’d be sold if it had extensions. Until it does, I’ll most likely be sticking with Firefox.
Let me know what you think Chris if you try it out!
Nope Colin, didn’t intend to show exclusive features. I like how Opera actually has menu items for the tabs though, as opposed to IE7 which simply says "open link in new tab" and is a background tab.
CTRL-T in IE7 doesn’t accomplish a new window with the history maintained?
Yes Kevin, I wish it had extensions too. It already has so much functionality out of the box though!
If this mysterious browser does have all the features that you are raving about, I will almost definitely switch over to it. I quite enjoy my script blocker with firefox though. How is the security on Opera?
Security is excellent as well…details are here:
http://www.opera.com/products/desktop/security/
And as I mentioned, you can block scripts on a per-site basis if you want. The granularity is awesome.
Just installed it, and right away I can already tell you a good and a bad. They auto-imported my bookmarks from Firefox, and even my tabbed bookmarks too! So that was nice. The bad is they organized it into alphabetical order. I’m sure a lot people can sympathize with me that they have their bookmarks in a certain order. There is no rythm or reason behind it other than that’s the order they added them as bookmarks. So they are so used to this order that even if it isn’t in any logical order they have no problem finding things. Now it’s all out of whack.
And what’s up with the tabs being above the address bar? Are they simply just going out of their way to make it look different from firefox? It’s making me mad that I can’t seem to get the tabs under the address bar.
Red hyperlinks? Now I’m really starting to think Opera is going out of their way to make it look different from IE and Firefox. If you are looking to get more business, I don’t believe that’s the way to go. Improve things, sure. But change things for the sake of changing them? Heck no.
Okay, here’s another feature for the list – Opera is damn near infinitely configurable. Want to stick the address bar above tabs? Here’s a visual tutorial that shows you how to do so:
http://nontroppo.org/-/media/mainbar.htm
Actually, Opera had tabs long before the other browsers, so if anything, it was Firefox/IE that changed the look! And there was probably another browser with tabs before Opera…it goes on and on…
More visual tutorials are here:
http://operawiki.info/VisualTutorials
Not sure what you mean by red links? And yeah, ordering of bookmarks probably isn’t something that can be fixed (at least not that I know of).
You really are addicted to facebook!
CTRL-T in IE goes a new tab (which can be blank or home page) but with no back history.
It was pretty much a clean install Megan, had to visit some sites for the Top 10 to work. Heh, though on my tablet, Facebook is still #5.
Thanks for clearing that up Colin.
Man.. opera iz da fastest browser i’ve tried. Wit my windows xp not a genuine copy my comp iz rily slow but opera iz still fast and dozn’t crash wen i use cheat engine (like firefox doz).