Some anonymous user made a comment with a link to an interesting text. I tested this stuff and it really works.
Skype user IP-address disclosure
1. Download this patched version of Skype 5.5
2. Turn on debug-log file creation via adding a few registry keys. Check it out here
3. Make "add a Skype contact" action, but do not send add request, just click on the user to view his vcard.
4. Have a look at the log file to find the desired skypename. The record will be like this for real user ip: -r195.100.213.25:31101 And like this for user internal network card ip: -l172.10.5.17
21:16:45.818 | T#3668 PresenceManager: | noticing skypetestuser1 0x3e54a539a91a19fc-s-s65.55.223.23:40013-r195.100.213.25:31101-l172 .10.5.17:22960 23d23109 82f328ff
5. Catch that skype user via whois service http://nic.ru/whois
6. Plug in their IP Address into the service to receive information.
The mentioned steps will help you to get the following information about a skype user: City, Country, Internet provider and internal user ip-address. Now, you can troll him about CIA and Mossad, he-he.