Hooray! According to the "official Gmail blog" Gmail lab features are now available in all supported Gmail languages - not just English!
Currently, there are 43 different lab features. I love and use these Gmail Lab features:
- Offline Gmail! If you like to try it, you'll need Mailplane 2.1-beta.
- Youtube, Picasa, Flickr previews in mail.
- Quick Links: Adds a box to the left column that gives you 1-click access to any bookmarkable URL in Gmail. You can use it for saving frequent searches, important individual messages, and more.
- Fixed with font: Adds an option to the reply dropdown menu that lets you view a message in fixed width font.
- Navbar drag and drop: Allows you to reorder the items in your navbar using drag and drop.
- Forgotten attachment detector: Prevents you from accidentally sending messages without the relevant attachments.
- Vacation Time: Lets you specify starting and ending dates for the vacation autoresponder.
- Custom Label Colors: Lets you create your own combination of colors for labels.
- Search Autocomplete: Provides search suggestions for contacts and operators as you type in the search box.
- Google Calendar gadget: Adds a box in the left column which shows your Google Calendar. See upcoming events, locations, and details.
- Google Docs gadget: Adds a box in the left column which displays your Google Docs. Shows recent docs, starred docs, and has fast search.
- Add any gadget by URL: Adds a "Gadgets" tab to Settings, where you'll be able to specify the URL of any gadget. This gadget will show in a box in the left column.
However, please do not use these lab features with Mailplane (they are not compatible):
- Custom keyboard shortcuts
- Hide Unread Counts
- Any signature feature (if you use Mailplane 2.1-beta HTML signatures).