I usually only send them to myself when I checking to see if the accounts are working all right - although sometimes if I think of something important regarding work whilst I'm at home in the evening I may send 1 to my work account via my mobile.
Sorry if I sound stern... but this isn't good practice. ( On top of being a software engineer, I took some network admin classes for a possible reconversion . )
It is generally wise not to store non-encrypted private information on 3rd party servers (Yahoo, Hotmail, your ISP email servers, f. ex.). There are many reasons, but for me the big one is that even when you think you deleted an email on your account, some copies of will still be available in redundant backups that are not yours...
Also, you should think of unencrypted email traveling on the Internet as a postcard. Anyone handling it can take a look at it. Depending on the law in your country, investigative action could be taken against you based on its content, without you being notified in the first place. :tut:
So, I have always loved computers, I have loved the Internet revolution and age, but the more I know and the more I think we need encrypted email and an international electronic signature system. For people as well as entities (companies, administrations, etc...).