Most of the people reading this post would have heard about the fall of Mt.Gox with Million dollars worth of Bitcoins and few recent problems of funds disappearing from some other trading platforms.
My bitter experience was with dogetipbot over Reddit. The founder of the Tipbot used the tipping funds to run his business and lost everything.
The amount of Doge coins which is lost is not much but not too low either but many people lost hundred thousands of thier funds.
Lesson -Never keep funds over online wallets unless you do day-trading.