Gmail is a free search-based web-mail service. It offers a full featured web-based email client with search capabilities, a mailbox with Pop and IMAP access, SPAM protection, display of email threads as conversations, a labeling and filtering system, an integrated chat, 7 GB of free storage, etc.
Gmail is free, with contextual ads. Gmail is also marketed as part of 'Google Apps', which is available in a free 'Standard' edition as well as a paid 'Premier' edition.
Furthermore the storage limit of Gmail can be increased by purchasing additional storage (starting from 5USD/yr for 20GB, for details see http://bit.ly/3by8d2).
Need to get caught up on your Gmail?
Try Gmail for mobile: http://www.google.com/intl/en/mobile/mail/
Keep your conversations going and get to any message you want - anywhere you are.