One of the other nice things in the endless list of kewl functions in Opera is the fact that is has a box next to the adresbox, in which you can search via a list of searchengines.
It's by default set to google, but it builds up the list from the search.ini file in the opera program folder.
I'm not really sure what all parameters do, but it does work:
[Search Engine n]
Name=&Everything2
URL=http://everything2.com/index.pl?node=%s
Query=
Key=e
Is post=0
Has endseparator=0
Encoding=utf-8
Search Type=0
Add this code to the search.ini file and make the number n the next number in the list of search-engines now you can search E2 via your Opera browser !!
When upgrading to a newer version of Opera, make a back-up of the search.ini. You might also want to use an other letter for the variable key since version 6.02 and up use the E for Ebay.
It's also OK to remove the other search-engines, Opera doesn't mind, I myself only use the Google and Everything2 search-functions.
Note: I have only tested this on version 6.01 and 6.02 for Windows.