Yahoo AddressGuard - Fighting Against Spam with disposable email addresses

Its good to see that Yahoo has found out a new way of preventing us from spam. Lately I was getting a lot of spams in my students account(IIIT students server) as well as yahoo account. Well, I can't do anything about students account (LOL at sysadmins), but yahoo's new AddressGuard concept may help reducing spams.
Though Yahoo is successfully able to filter spams to my bulk folder, still I can't ignore them all as some of my important mails are also labeled as spam and moved to bulk folder... specially mails from my students id.... again I think a fault of sysadmins.
The new concept is : You can create several email ids of the format basename-keyword@yahoo and then use different ones at different places. Messages to all ids will come into your inbox or separate folders as u choose. Once you see a particular email id is the reason for spams, then simply delete it.

Good ... No! My old original email id is still valid and its already been targeted for spams. How do I deal with that? I think Yahoo people must find an answer to that. I was all delighted to see the new service but the problem is still not solved for old users who are already been targeted for spams.
While writing this post, with the help of googling I found out yahoo AddressGuard, in a modified form, already existed for paid users. Also gmail also has something similar - aliases... but their method is not so good. Gmails aliases are of the format gmailid+blabla@gmail.com. So spammers can easily extract the original email id from this alias (string before the plus is the original gmail id). But yahoo's format basename-keyword@yahoo.com is different coz basename has no relations with your original yahoo id.
Read the official thing here. You can get a different perspective about it here and here.

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