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, 10 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.