Gmail is becoming more popular by the day, but it's far from perfect. Let's take a look at some tools that will extend its functionality and makes it an even more worthwhile service.
For the desktop
gBooks: If your browser's bookmarks folder doesn't do enough for you, this clever tool turns your Gmail account into a bookmarks server. It makes your bookmarks available to you any time you log in to your Gmail account from anywhere.
gCount: If you don't feel like firing up a browser to check your Gmail account, use gCount. Running on Mac OS X, the lightweight app sits in your Dock and gives you real-time updates on how many e-mails you have in your in-box.
Gmail Drive: Gmail Drive (for Windows) creates a virtual file system on top of your Gmail in-box. It lets you upload documents, photos, or practically any other file to Gmail Drive. Those files are available for download anywhere you can access Gmail.
Gmail Loader: Gmail now makes it easy to import e-mails to your account, but one solution for Windows or Linux PCs works just as well. This software reads the e-mails in your current e-mail program (most of the well-known services are supported) and automatically forwards them to your Gmail account. E-mails can be sent to either the in-box folder or sent items folder.
gMail Notifr: Gmail Notifr is an open-source tool for Mac OS X that allows you to check your Gmail in-box at specified intervals. It includes Growl and sound notifications. You can check multiple accounts simultaneously.
gotMailG: gotMailG is a dashboard widget that just tells you how many unread messages are waiting for you--useful if you don't want your primary workspace cluttered with Gmail icons or alerts.
GPeek: If you don't want to read through every message but want to see what just came in, use GPeek. The service lets you see the subject of an e-mail, the sender, the time it was received, and the first few lines of the message. It supports multiple accounts, so you can check all your e-mails in one sitting.
Jiffy Gmail Email Creator: The Jiffy Gmail Email Creator makes configuring and maintaining your Gmail account easy. It allows you to create an auto-responder without going online. You can also forward messages automatically, use random names, enable POP3, and use multiple exporting options from your desktop. It's for Windows only.
Send to Gmail: Send to Gmail (for Windows) makes it easy to upload any file on your hard drive to Gmail in just two clicks. Simply find the file you want to upload, right-click on it, and you'll be given the option to "Send to Gmail." Once you click that option, the file is sent directly to your Gmail account.
For the Web (Firefox extensions)
Better Gmail 2: Better Gmail 2 combines a variety of Greasemonkey user scripts to enhance the functionality of the e-mail service. The software provides users with the option to use attachment icons and macros, place the in-box count first, and force an encrypted connection. It basically combines the best of Gmail Labs add-ons and puts them into one package for you.
Drag and Drop Upload: If you don't want to search around for files and you don't like the Gmail file attachment process, use Drag and Drop Upload. Simply drop files into the attachment box or the "browse" button for attaching files on Gmail and you're set. The add-on will do the rest.
Gmail Manager: Gmail Manager lets you manage multiple Gmail accounts in Firefox. It also alerts you to new mail without viewing your in-box. All your account information, including unread messages, saved drafts, labels, and more are available though the add-on.
Gmail S/MIME: Once you install the Gmail S/MIME add-on in Firefox, the tool will allow you to send and receive encrypted S/MIME messages in the e-mail app. It works with most versions of Outlook, Thunderbird, or Mail.
GSpace: If you're looking to use Gmail as an online storage space, GSpace is a fine alternative to the aforementioned desktop software, which provide the same service. Simply install this add-on and it will be available in your Firefox "Tools" menu. Once you run the add-on, it will turn Gmail into an FTP client, allowing you to upload files and store them in your account for online access at a later time.
GTDInbox: With the help of GTDInbox, you can improve your use of Gmail. The add-on turns e-mails into tasks, giving them a priority and allowing them to be viewed by project, context, or person. It also offers a popup command box that lets you preview, archive, or delete messages in just a few clicks. It streamlines many of Gmail's most-used features and works well. Try it out.