After I read (and respond to) email messages, I either delete them or file them away in a folder. I *hate* for a whole bunch of email to be all piled up in my inbox and I don't feel the need to keep every piece of correspondence people send me.
Mr. SingLikeSassy has never deleted an email. Not ever. His inbox has about 8 million emails in it. But, he also doesn't respond to email. And doesn't read 98 percent of the email he receives. I have to put some variation of "!!!READ THIS!!! VERY VERY IMPORTANT!!! in the subjectline to get him to open MY email messages and I'm married to him! And believe me, even with that included in the subjectline it still does not guarantee a response. I can count on one hand how many emails he has sent me.
What's your email style? Do you keep everything, reply to everyone, purge, hoard?