PC Stats has an article about exploding capacitors.
While at first I dismissed it as a "one timer" I quickly changed my mind after looking at their poll where 40% out of 600 people said they have had a capacitor blow. Then after looking in their forums where also quite a few people said they had blown capacitors I got more interested...
As a side note The Inquirer ran a story this last October about this. If you put the words "Capacitor" in their search-engine the word "Abit" comes up quite frequently. So the plot thickens...
If you want to see more pics visit this site, which also (at a cost) can repair your mobo.
Be sure to post a comment if this has happened to you.