There's a million of these URL-shortening services. Other good ones are the classic http://TinyURL.com, the subdomain-based http://notlong.com, and the newer, simple, quick http://rurl.org, and the now-popular http://urlTea.org, which lets you "semanticize" the shortened URL by including descriptive text at the end. To me, SnipURL -- especially the new release -- beats them all in terms of features and ease of use. Every once in a while the site goes down, though, which strikes fear in my heart.

As far i know, the shortest url redirection service is http://dn.vc and it feature like masking and keyword.

Nice one, thanks for the tip, macusri.

None of the "million" shortening services offer anywhere near as many features as Snipr, or are anywhere near as professionally done. The "dn.vc" thing is just plain weird. When you send a shortened URL to friends you want them to be able to trust it. Stuff like tinyurl is used by spammers all over the place which is why it is banned by many Asian ISPs. Snipr is the only one that is on top of all the junk stuff. (Disclaimer: I'm a sys admin for MySpace and having had to deal with many of these services, pretty much the only one I can recommend is Snipr. The guys are excellent.)

I should also comment that since 2.0 was rolled-out, I personally have seen zero downtime.