Porsche is certainly on a multi-year wave of price increase. Every generation has gotten more expensive. Even some newer cars barely drop in price before returning to MSRP levels. I'm not sure how long it will carry on for.

Some Corvettes are rising in price as well, namely the C5 Z06 or C6 Z06, though at a slower pace. They make great race cars, but aren't as nice inside as the Porsche's. However, I don't think they've peaked in value on the used market, so they can be a good buy.