Use a Unique Address
An e-mail address containing both numbers and letters can help prevent spam. Many spammers use "dictionary attacks" to e-mail many possible name combinations at large Internet Service Providers (ex: Verizon, AT&T, Earthlink...) or e-mail services (ex: Hotmail, Yahoo, Lycos...), hoping to find a valid address.
Also, use a unique screen name that is not associated with your e-mail address if you chat online. Screen names are accessible to spammers so don't make it too easy for them to guess your e-mail address.