Forget the stock market . If you're in the possession of a NYC taxi medallion, you're sitting on a goldmine. A retiring Pakistani driver who'd been driving a cab in New York for the last 25 years sold his medallion Wednesday for a staggering $600,000 -- an all-time record for such a sale. The medallion, which gives cab drivers the right to operate legally in the city, cost $30,000 when it was purchased in 1981. The new owner is a taxi fleet operator who already owns somewhere around 100 medallions.Prices have been steadily rising in recent years, and at the last city-held auction , medallions fetched upwards of $500K. Experts feel that the city could bring values down to a more realistic level -- around $300,000 -- if they added 5000 new ones to the pool. Until that happens (if it happens at all), expect to see more astronomical sale values as medallions change hands. There's a limited number of the things out there, and right now, the demand appears to be off the charts.At this rate, it's probably just a matter of time before we see a reality show about this. Flip This Medallion, anyone?We covered one of last year's big-money medallion cars here [Source: NY Post, via GM Inside News