Greg Hyman, co-creator of Tickle Me Elmo and a longtime toy inventor, died on May 1 at age 78 in Boca Raton, Fla. The electronics wizard partnered with Ron Dubren to develop the giggling plush toy, which debuted in 1996 and triggered retail chaos — Tyco's initial 400,000 units sold out by the day after Thanksgiving.

The toy rewrote retail history. Tickle Me Elmo retailed for $29.99 but was scalped online for as much as $7,000. Shoppers trampled a Wal-Mart clerk in Canada during an overnight shipment, and Tyco deployed Boeing 747s to keep shelves stocked amid the frenzy that defined the 1996 holiday season.

Hyman began licensing toys in the late 1970s, partnering with Larry Greenberg on hits like Major Morgan for Playskool. After Elmo, he and Dubren didn't collaborate much. Dubren said they gained creative freedom but didn't amass vast personal wealth from the cultural phenomenon they helped build.