I don't know about Query Analyzer, I haven't used it in a couple years now, and it gives me chills just to think about it.

But in Microsoft SQL Server Management Studio ( which kills off QA as well as Enterprise Mangler ), we seem to have unlimited undo. Yesterday I produced a stand-alone DTS package ( persisted as a structured file, and not managed by the server ), but now I've been asked to add one more thing to the package. I'm not sure if it's possible to get into the designer for the DTS file I created, but thanks to Ctrl-Z, I got all my code back.

Also, for anyone who works with indexed views a lot, if you go to Tools -> Options, you can tell the client tool to automatically set ARITHABORT on when you launch a new query window!!

As long as I'm sharing cool tips, I hope everyone knows about selecting a table name and then hitting Alt-F1? That one works even in Query Analyzer.

Thanks for the tip mate.
BTW, you can use repository, every time you make a change, you submit your change. And you can switch back to any revision just 2 clicks.