How can I find unread messages in Google's Gmail?

In typical Google fashion, there are quite a few tricks you can do with a Gmail search, though you can't yet convert Yen to Euros like you can in the main Google search box (really. Try searching for 100 yen in euros. Cool, eh?)

The main shortcut you want with Gmail is label:unread, but as it turns out, there are quite a few different labels, both those you define for yourself and those that are already defined by the system. For example, in addition to "unread", there's also a "read" label, so you could also search for label:read.

Turns out that the navigational elements on the side of the main Gmail display are all label shortcuts, actually, so "Inbox" is label:inbox, and "Sent Mail" is label:sent. Better yet, you can combine them, so if you have a custom label called, say, "treasurebox" and want to find all the unread messages therein, your search would be label:treasurebox label:unread.

In exactly the same way, chats are all archived and they are known as label:chat, so a search through all your chat archives for, say, the word "asterix" would look like label:chat asterix.

Here's what I see when I search my Gtalk chat archive for the word "blog":

Neatly done. And don't forget you can always find all chat records with a single person by searching for their name (e.g., label:chat andy jenkins) and with email you can also search by from:, to:, subject: etc., in addition to the nifty label searches I've shown here.

Want to find all messages from someone at Microsoft that mentions cats in the subject line? That'd be from:microsoft subject:cat Same search, but across all message content? from:microsoft cat. All of those that might be unread? from:microsoft l:unread cat (notice that I demonstrate a trick here: you can abbreviate "label" to "l" if you're really lazy. There are lots of abbreviations like that available if you're willing to experiment a bit!