You might want to be careful if you're chatting over Skype with pranksters. There's an absurdly simple string of text that can crash Skype clients.
The string is, simply:
The bug was first spotted on the Skype Community Forum as well as other bug reporting sites. If you're recieve the message using an affected version of Skype, which includes certain Windows versions as well as the iOS and Android clients, your Skype app will shut down and crash without displaying the message. Because Skype loads previous conversations when booting up, the same message will continue crashing your client.
Skype is aware of the denial of service issue and is working on a fix. When I tried to replicate the issue, the messages didn't go through and instead displayed a yellow exclamation point next to the message. So the problem might already be fixed on Skype's end, although it might just be a stopgap measure before Skype can issue a patch. The bug also doesn't seem to affect Macs and certain Windows versions.
Unfortunately, the best way to get your Skype working again if you've been affected is to ask the sender to delete his message. Otherwise, you can flood your chat with photos or other large messages until the 'http' string is pushed into the archive.
This bug is reminicent of the Effective Power bug, a line of text that can crash iPhones discovered last week that still -- incredibly -- hasn't been fixed. One key difference is the bug that affects iPhones relies on a trick using Arabic characters that change the direction of text from left to right. The Skype bug doesn't rely on the same problem. Instead, it appears to take advantage of an issue with URL handling.