Can I use RCX sensors and motors with the NXT brick? I have a bunch of motors and sensors from the original Mindstorms set. It seems a shame I can't use these with the more recent NXT set. Are there any unofficial modifications that allow you to convert the cables?
LEGO used to sell Converter Cables for Mindstorms NXT at a price of £8.99 / US$9.99 for 3 cables at their online shop, they can still be bought online from stores like Bricklink.



Considering the price of each cable converter it may be worth purchasing newer sensors/motors that are more advanced. The NXT system cables are separate from sensors and motors and come in different lengths.