I didn’t realise until recently that you could search your hotmail inbox using keywords to narrow the search. I’m talking about the web version of Hotmail, not when you’re accessing it via a client application like Outlook.
For example, let’s say you wanted to find an email from your friend John Lyons, that will have been filed in a folder called “School”. Just type “from:Lyons folder:School” in the search box at the top right of your hotmail webpage:
It works with “to” as well, and of course you can search all folders by omitting the “folder” keyword.
[Update: "Subject" works too, so for example looking for emails with a subject containing the word "tickets", you would enter "subject:tickets"]
With my inbox having well over 10,000 messages, and multiple folders, this kind of search refinement is really useful to me. It’s really quick too.