Google is famed for its experimentation. One of the most fertile grounds for such testing is the Labs section of Gmail (or Google Mail depending on where you live) and it's possible to completely customise the way you use the service.
Gmail Labs is, in Google's own words, "a testing ground for experimental features that aren't quite ready for primetime".
As such, the items here aren't always the most reliable of add-ons, but these 12 are definitely worth a look. Some are extremely clever or help you avoid email faux pas, while others are simple productivity tweaks.
You can turn on any of these features from the Labs tab under Settings in Gmail, or click the green conical flask icon in the top-right of your Inbox window.
1. Don't forget Bob and Got the wrong Bob?
The two strangest-named Gmail labs add-ons are also one of the cleverest. "Forget" will let Gmail suggest other contacts you might want to include on an email based on those people you email most often.
Better still "Wrong Bob?" will check if you meant to include Bob Smith rather than Bob Jones – useful for making sure you don't email your boss with NSFW material. Not that you email that kind of stuff, obviously.
2. Clever previews
We've gathered together a few add-ons here, but Labs enables you to preview YouTube, Picasa, Flickr, and Yelp content directly within Gmail. Each is a separate add-on you'll need to enable.
So if somebody sends you a YouTube video, you can view it directly from within your email. Lucky enough to live somewhere with Google Voice? You can play messages back directly from the notification email as well.
3. Message translation
Turn on this clever new add-on and Gmail will translate any email you receive in a language other than your own. We wonder if it'll work for Americans trying to understand Brit-speak?
4. Title bar tweaks
This is the kind of simple but oh so useful tweak we love Google to provide. It changes the browser title bar from "Google Mail - Inbox (20) – firstname.lastname@example.org" to "Inbox (20) - email@example.com - Google Mail". Eh? Well, it means that even if your browser window is minimised (or you have a lot of tabs open), you'll still be able to tell how many new emails you've got.
Probably Gmail Labs' most essential add-on, Tasks shares a to-do list that's common with Gmail, Google Calendar, iGoogle and on gmail.com/tasks on your phone. If only it would sync with our corporate Microsoft Outlook tasks (sigh). Tasks has actually been so successful that it has now graduated from the Labs to become a Gmail feature proper.
6. Undo send
Really? Yep. If you've sent sexy speak to someone you shouldn't have, this add-on prevents divorce/unemployment/being taken to a tribunal. It's a failsafe that can stop messages from being sent for a few seconds after you hit the send button (a little "cancel" appears alongside the "sending" message). One of those things that you hope you'll never need, but it could save your life if you have a little "issue".
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Dan (Twitter, Google+) is TechRadar's Former Deputy Editor and is now in charge at our sister site T3.com. Covering all things computing, internet and mobile he's a seasoned regular at major tech shows such as CES, IFA and Mobile World Congress. Dan has also been a tech expert for many outlets including BBC Radio 4, 5Live and the World Service, The Sun and ITV News.