Opera already has an adblocking feature built-in. go to "Tools > Preferences > Advanced > Content > Blocked Content to see all the blocked websites. you have to manually edit the think though. but if you don't feel like doing that, then just find urlfilter.ini(either in %appdata% or in the Program Files directory depending on instalation settings) and copy/paste. blame Microsoft for that. Opera always doesn't display MSDN pages because Microsoft can't realize that Opera supports the web standards. and AFAIK, Microsoft serves Opera an old and incompatable stylesheet for Opera to use. i can't say for sure that Microsoft does that because that's just my guess. however, i do know that something similar used to happen with Hotmail 2 years ago.and as for Firefox extensions, that's a horrible idea IMO. sure extensions are really great, but the end result is that you get slower startup, slower browser(in some but not all cases), and more memory usage. Opera has a ton of functionality which doesn't use up a lot of memory and doesn't mess with my browsing experiance. btw, if anyone is interested, here's a list which shows 150 firefox extensions. it pretty much shows if Opera has similar or better functionality. http://files.myopera.com/Rijk/blog/extensions.html