Hundreds of passengers were on their way from India to Britain via Comtel Air, when they were told they'd have to cough up gas money if they wanted to reach their final destination. According to the Associated Press, paying customers were stuck in Vienna for six hours, where some claim they were asked to visit cash machines for money. Because that's exactly the type of customer service that gets people to fly with you again.
By the way, this is an airplane we're talking about, not your boy's monochromatic '95 Civic. Instead of having to raise a collective $25 or so, passengers had to produce over 20,000 pounds, which equals about $31,000. If you were considering flying with Comtel, do yourself a favor and stop.