To me it´s a strong sign of passion for racing when famous and successful racing drivers who´d driven the most desirable, powerful and expensive race cars during their career feel the desire to rebuy their old race cars in which they started racing.
As an example, the three times Le Mans 24 Hours winner Marco Werner bought back his Monaco winning Ralt F3 car and owns his old FF1600 (which he self constructed and built back then )
Another example is former BMW works driver Jörg Müller who bought back his Van Diemen FF1600 which he raced in the German Championship in 1988. It was the very car, in which Ellen Lohr won the German FF1600 Championship the year before.
IIRC David Coulthard still has some of his old racing cars from FF1600, F3, F3000 as they were on display at the (now closed?) David Coulthard Museum.
Any more drivers with a soft spot for their old machinery?