Gmail can be tweaked almost endlessly with various Firefox and Chrome extensions, and offers some pretty nifty Labs options too. However, we’ve taken a look at some simple tips, tricks, tweaks and shortcuts you can use without going down the plugin or experimental route.  These 10 features will help you get so much more out of the webmail service, from an enhanced chat experience, to smarter filters, to offline access.  Have a read through now and let us know any neat GmailGmail hints you’d like to share in the comments box below.  Gmail’s instant messaging Chat function is one of the more basic options around, but there are a few bits of formatting you can use to add nuance to your online communication.  To bold a word, asterisk it like this: *MashableMashable*  To add italics, just underscore before and after the word like this: _Mashable_  And to strike a word through, add hyphens before and after like so: -Mashable-  You’ve no doubt noticed the “Web Clips” line of text that appears above your Gmail inbox which contains news, blog posts, ads and other info. But did you know you can personalize it to make it more relevant to you?  Simply go to “Settings” on the top right of your screen and select the “Web Clips” tab. From there, you can search, browse from the categories, and add and remove items to your heart’s content.  Although technically you only have one Gmail address, you can create as many variations of it as you wish to help manage your incoming mail.  You can do this by adding a word after your name with a plus sign (if the site you’re entering the address into allows it). So, yourname+newsletters@gmail.com, yourname+shopping@gmail.com, and so on.  This alias system then comes into its own if you also set up filters to direct those messages where you want them. For example, they could skip the inbox and be archived, have a label applied, be forwarded to another account, and so on.  To set up a filter, go to “Settings,” hit the “Filters” tab, select “Create New Filter” and follow the simple steps from there.  This is a useful option for anyone on the go, as it allows you to access your Gmail account when you’re not connected to the web. You can search, read and compose e-mails when you’re not in a Wi-Fi zone, and Gmail will simply auto-update (and send/receive any new mail) when you next reconnect.  To set up your Gmail to be available when you’re offline, you have to download Google Gears, but it’s a simple process from within Gmail. Head over to your “Settings” menu, hit the “Offline” tab, and check the option to “Enable Offline Mail for this computer.”  Once you save the changes, Gmail will auto-prompt you through the process and even gives you the option to create a desktop shortcut for quick access to Gmail when offline.  Gmail handily saves your chat history for conversations with other Gmail users and makes them searchable too (use the search term “is:chat” to look for a keyword term). But there might be times you want to chat and not have it recorded.  To chat “off the record,” open a chat window with whom you want to talk, click on the “Actions” drop down menu and select “Go off the record.” The person you’re chatting with will be notified of this change, and you can go back on the record in the same way.  Gmail offers a free NotifierGmail Notifier as a quick download that will alert you with a visual pop-up and audio cue when new mail has arrived, even if you don’t have Gmail open in a browser.  It automatically checks for new mail every two minutes, with the icons changing to show unread mail in case you miss the notification. The app is available for both Windows PCs and Macs. It should be noted that downloading this will also make Gmail your default e-mail program, which you might need to consider if you don’t want this to be case.  While Gmail’s keyword search works well enough for basic queries, there are some advanced options that can help refine your process.  For example, entering to:me is:unread in:inbox will bring up any unread mails in your inbox. Entering has:attachment will show you a list of e-mails with files attached, and after: 20/08/2010 before: 25/08/2010 will offer up a list of messages from that specific time period.  You can view the major search operators over at the Gmail support site — it’s well worth memorizing a few.  Gmail’s “Priority Inbox” functions by highlighting what it considers your most important mail, and has launched to positive feedback. But you can improve it as time goes on.  In order to help Gmail better recognize what really is important (and conversely, what isn’t), simply select an e-mail message and hit the little plus or minus arrows at the top of your inbox.  Useful for prioritizing replies if nothing else, there’s a setting in Gmail that will enable you to see if a message has been sent just to you, or a mailing list.  To activate it, go to “Settings,” then scroll down to “Personal level indicators” and select “Show indicators.” This will now mean that every message in your mailbox shows how many recipients there were at a glance.  No arrows will show if the message was sent to a mailing list, “>” shows up when the message was sent to you and others, and “>>” indicates the message was sent to just you.  And finally, on a lighthearted note, did you know there is a free online game you can play that’s inspired by Gmail?  “Galactic Inbox” was created by Paul Truong, a creative technologist “in part, as a ‘thank you’ to the Gmail team for their ongoing work to improve the webmail galaxy.” If you want to show the gTeam some love too, then hop on over and have a play!  - 5 Great Unofficial Gmail Themes - HOW TO: Undo “Send” in Gmail - 5 Ways to Spice Up Your Gmail Signature - Gmail Priority Inbox: 5 Tips for Better Productivity - HOW TO: Give Your Inbox a Master Cleanse
Looking to boost your Gmail productivity without all those newfangled browser extensions? These 10 easy tweaks will make you a Gmail power user right out of the gate.