According to page 167 of John Rich's new book Warm Up the Snake, the show offered a monetary prize for good MacGyverism ideas they could use in the show.

The story goes that a young fan of the series suggested that MacGyver could patch up a vehicle's radiator by cracking egg whites into the radiator. This trick was used in the Bushmaster episode and the young fan was rewarded.

Although they had staff appointed to read all the letters sent in for this competition, few usable ideas where ever obtained through this method.

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Didn't one fan also come up with using a lightbulb filament to pick a lock, as Mac did in A Prisoner of Conscience? As we saw on Mythbusters, it works, albeit a bit slower than it did in the episode.

That specific MacGyverism was cited in an article at the time, as having been submitted by a fan. I think it was the TV Guide article that also described RDA using his "Swiss Army Bench" to break into his own house when he'd locked himself out.

The slow performance on Mythbusters was partly due to their not having much practice in picking locks . . . I'm amazed they pulled it off at all.