Best way to crack emails?

[Mem5]

Hi,
Please share here your hints about cracking emails.
I personally use :
- facebook names wordlist (left side) + wordlist of email domains (gmail.com, hotmail, etc., right side) using combinator attack
- pure brutoefroce (left side) + wordlist of email domains (gmail.com, hotmail, etc. right side) - very slow.

Both are not very efficient.

Do you have any advices / hints you could share?

Thanks.