Forward all your YMail to GMail. You can also spoof your GMail account to display your sender name as your YMail using the following
http://mail.google.com/support/bin/answer.py?hl=en&ctx=mail&answer=22370
My set-up is that all my med school email is sent to a single account that is ONLY for med school apps. We'll call this compassmedschool2009@gmail (which it isn't)
I don't log into this account EVER. I don't remember the password for it, either. Oh well.
All that mail is auto-forwarded to my main, which we'll call compass@gmail (which it isn't)
If I need to, I can reply with the compassmedschool2009 address without having to log into the super-long name. They'll reply back to the medschool address and I'll receive it on my main address regardless. Win, win!