Last month Opera gave away registration codes for free, now they’re removing the adds AND THE LICENSING FEE! Check it out here. Premium support is still something you pay for.
I like that they use the Bittorrent technology to distribute Opera (as an alternative to regular downloads!).
One feature I particularly like about Opera is the ability to take notes. You don’t need a seperate program, just select text from a webpage, and tell Opera to create a note of it. You will have the text in the note, and Opera will remember from what URL you got the text from.