This is an extremely cool hack that you can use to get a Yahoo Mail Beta invite. Only if you already have a Yahoo Mail account ! Here are thse steps…

1. Login to your Yahoo! account as usual .
2. Click on My Account ( top of the page , to the right of the Yahoo logo )
3. You will be asked to enter your password again . Do it
4. On the next page , click on the first Edit button from the top ( the one on the first yellow line , the line that says Member Information ) .
5. Close to the bottom of the next page , there is a link next to the words Preferred Content ( under General Preferences ) . Click on it
6. As the new setting , choose Yahoo! United Kingdom . ( if you already have it set to UK ,pick another one , i don’t think it matters which one you pick , just that you change it )
7. Click on one of the Finished buttons ( top or bottom )
8. You will be shown the Yahoo! ToS . Just click I Accept
9. You will be taken back to the page from step 4 . Click on one of the Finished buttons again .

You should now get a page with a button that says Try Beta Now Just click it and you’re done .

It worked for me! Except now vendors are peddling their goods in Euros and British pounds! Thanks, though!

tried it but went back to the old version because it was slow. Hopefully they'll fix this.