This is a very different world from the one in which IE6 rose to dominance. We're in no way in a Webkit monoculture right now – Trident and Gecko aren't going anywhere any time soon!
Specifically addressing Opera: the smaller-audience engines that have had their chance but not done much with it should be left behind, making room for new small players to step in and take the reins. I can't wait to see some new players in this space.
> Rails 2 introduced a new default session storage, CookieStore. CookieStore saves the session hash directly in a cookie on the client-side. The server retrieves the session hash from the cookie and eliminates the need for a session id. That will greatly increase the speed of the application, but it is a controversial storage option and you have to think about the security implications of it:
Zsh has an autocorrect feature that suggests different spellings of your command if it can't find anything exactly matching it. I'm sure that I recall hearing of similar functionality available for bash, too.
Also, recent versions of Ubuntu include shell aliases that will search for packages related to missing commands. I'm sure that if you don't use Ubuntu, you could rip this functionality out and port it to whatever packaging system you use.