1 - Build a database of short to unshortened URLs as a backup in case that one of the shortening services goes under.

2 - Such a service can be useful for anyone who wants to know where the URL points to without clicking it (or without the skills to unshorten it themselves).

3 - It could allow for batch unshortening

4 - A database can still unshorten URLs that no longer exist etc..

I think I'm one, because I don't know of any way to unshorten these tiny URLs without visiting them or using some such service.

If you know of one, could you enlighten me? Thanks...

     $ curl -I http://tinyurl.com/9a4xj6
     HTTP/1.1 301 Moved Permanently
     X-Powered-By: PHP/5.2.8
     Location: http://www.hostingcoupons.org/godaddy-coupons/
     Content-type: text/html
     Date: Fri, 24 Apr 2009 21:26:48 GMT
     Server: TinyURL/1.6

     >>> import urllib
     >>> u=urllib.urlopen("http://tinyurl.com/9a4xj6")
     >>> u.url
     'http://www.hostingcoupons.org/godaddy-coupons/'
     >>> 

Java sadly doesn't have a decent non blocking dns resolution system :( On a restart, Mibbit needs to do a few thousand DNS lookups... and quick. I can only stand a thread pool so long.

Well there's your problem! :P

Yeah. Handling 1000+ http requests a second on a single 1.4GB VPS is lame isn't it.

Java rocks. But it's not for beginners.

Sure, this is not a complete solution (there are videos in sites other than Youtube, Metacafe, etc., and NSFW content in just too many websites), but would help in very many cases.

Actually I'm surprised not so many people are concerned about the security implications of having opaque URLs (there's been a lot of talk about this recently, but very little action AFAIK).

I've been thinking about this lately and thought a Firefox extension might be of help. I was just planning to shake off my laziness and learn about how to make an extension so I could make this one.

A positive response to http://news.ycombinator.com/item?id=577896 might make this unnecessary, but then it might not...

If it did caching, it would also act as a proxy. That would be nice if I decided to build a greasemonkey script/firefox add-on to automatically unshorten things; I wouldn't necessarily ping the counters attached to every shortened URL that loads with a page.