There are few TLDs who ever allowed the registration of one-letter domain names, and most of them have raised the prices sky high. NUnames now wants EUR 500/year for 1-letter delegations and that's one of the cheaper variations.
I don't know of many geeks/private individuals who own a 1-letter domain, so I would consider it a loss to give up y.nu. But 500 EUR just for the fun of having a short e-mail address is a luxury I won't be able to afford forever.
My idea: if there are a few nerds around interested in doing something nice with this domain (short URLs for service you want short, like URL shortening or the my-IP service on ip.y.nu - and of course short email-adresses) let's share the cost...
So: if you would like to have a short email (like a@y.nu) including a matching A-record like a.y.nu or have any other nice ideas what to do with a short domain name, and are willing to share the yearly cost, mail me at r@y.nu (try to mention y.nu in the subject) as long as this is still possible :) Expecting about 20 participants about 20 EUR/year (possible a little more for most wanted subdimains/usernames) should be realistic. In the hope to get this to work...