This post is a comparison of the various email clients available on mac osx (and some mac osx email clients and sparrow alternatives if you are looking for them – Ive included sparrow in the list aswell so that others might learn its awesomeness)

1) mail.app

features:
imap, pop, exchange, gmail, hotmail, yahoo mail
price: included in osx for free
major bonus: all emails are included in your spotlight searches