Google labs feature u must enable in gmail

Recently i was just going through the lab features for gmail. I have had a few lab features before. But I feel these two lab features is must enable if you have gmail account.  

Offline Gmail:

So even if you're offline, you can open your web browser, go to gmail.com, and get to your mail just like you're used to.

Once you turn on this feature, Gmail uses Gears to download a local cache of your mail. As long as you're connected to the network, that cache is synchronized with Gmail's servers. When you lose your connection, Gmail automatically switches to offline mode, and uses the data stored on your computer's hard drive instead of the information sent across the network. You can read messages, star and label them, and do all of the things you're used to doing while reading your webmail online. Any messages you send while offline will be placed in your outbox and automatically sent the next time Gmail detects a connection. And if you're on an unreliable or slow connection (like when you're "borrowing" your neighbor's wireless), you can choose to use "flaky connection mode," which is somewhere in between: it uses the local cache as if you were disconnected, but still synchronizes your mail with the server in the background. 

Isn't this really great.It is according to me..

So how to enable:

1.Click settings,then select the labs tab.

2.Then enable the offline gmail feature and save the settings.

3.Now you will find a link on top right side of the gmail window named offline gmail.

4. Click the link and follow the instructions.