RCTrucker7 writes with a link to a Maximum PC story, which begins: "Details of Dell's surreptitious collusion with RIAA (Record Industry Association of America) have emerged. Apparently, the computer manufacturer disabled the Stereo Mix/Mono Mix/Wave Out sound recording function on certain notebooks to assuage RIAA. The hardware functionality is being disabled without any prior notice and one blogger has even alleged that he was asked by Dell's customer support staff to [shell] out $99 if he desired the stereo mix option. Gateway and Pac Bell are the other two manufacturers to have bowed to RIAA at the expense of their customers' satisfaction and disabled stereo mix without warning."
(There are some workarounds posted in the comments of the linked article.)