Use One Email Address with Multiple Twitter Accounts
If you have two Twitter accounts - @labnol that you use for writing personal tweets and the other account is @HundredZeros where you tweet about free ebooks.
Then you should probably aware of the fact that you cannot associate the same email address with multiple Twitter accounts. Try that and Twitter will throw up an error saying - "Email has already been taken".
There's however a simple workaround that will let you use the same email address with all your Twitter handles- the only condition is that you should be using a Gmail or Google Apps email address.
In Gmail, you can add a dot (.) anywhere in the username and all emails address to that new alias will still reach your mailbox. For instance, if your original email address is email@example.com, any emails sent to firstname.lastname@example.org or email@example.com will land in your mailbox because Gmails ignores periods in the email username.
And that's what you can use to trick Twitter. Twitter will consider hello@gmail and he.llo@gmail as two separate and valid email addresses even though they point to the same Gmail Inbox. Thanks CreativeBits.org.
When you open an account in Gmail, you automatically get another valid email address that uses the googlemail.com domain.
So if you only have two handles on twitter, you can use the gmail.com address with one handle and the googlemail.com address with the second handle.