The main reason for ensuring a correct / working e-mail address is for marketing. A valid e-mail address is like gold nowadays whether you plan on selling the addresses, sending out adverts in your usual newsletter or just as a future resource.

One effective way of acheiving this and one I plan on using more in the future is to scrap login names completely and have users login using their e-mail address / password. If you want to take this one further, you can send a randomly generated password to the e-mail account on registration rather than let the user choose their own. This way your mailing list is going to be about as accurate as it can be.

But... as usual - those lovely users of ours have solved this problem already: :)

Bugmenot.com - login with these free web passwords to bypass compulsory registration

Alan