Safari 5 supports extensions now…here are some I’ve downloaded so far:
SafariRestore automatically restores your previous browsing session. That Safari still doesn’t do this by default is beyond ridiculous.
NoMoreiTunes stops Safari from opening iTunes when you visit an iTunes Store link. Again, Safari’s default behavior is not optimal here.
I got all these from the Safari Extensions Tumblr, which is a bit overwhelming. I wish they’d curate a bit more instead of letting everything through. To that end, are you using any good extensions people should know about? Do tell.