The following utility allows you to decipher an obfuscated IP and make it easier for yourself to track down spammers, scammers and software pirates.

IP obfuscator/de-obfuscator: http://www.odditysoftware.com/page-webtools5.htm

Another link: http://www.treachery.net/tools/obfuscator.html

Furthermore, here is an interesting tutorial on “How to obscure any URL”.
This is a description of what obfuscation is (from OdditySoftware.com):

So you don’t understand what Obfuscation is? Lets look at an idea of employing it as URL Obscuration.

For example, start with the regular Google URL: http://www.google.com
And convert it to IP: http://64.233.161.104
Then add some bogus authentication gibberish: http://www.msnbc.com@64.233.161.104
And convert the real URL into a single number with the calculator above so it looks like a document on the MSNBC web site: http://www.msnbc.com@1089053032 Paste this link in your browser, and where does it go? That’s right… Google.

Believe it or not, this is just the tip of the iceberg. In some browsers, even the IP address numbers can be expressed using “percent sign” ASCII encoding.