For transparency the below is entirely from GPT-4. All successful except for the Google Lunar XPRIZE. It's notable that these prizes ranged from $7M (Ocean Discovery XPRIZE) to $30M (Lunar XPRIZE), so the stakes have really gone up for this one.

Ansari XPRIZE (2004): Aimed at private spaceflight, won by Mojave Aerospace Ventures' SpaceShipOne, demonstrating private manned spaceflight.

Progressive Automotive XPRIZE (2010): Focused on energy-efficient cars. Edison2’s Very Light Car won in the Mainstream Class, and Li-ion Motors’ Wave II and X-Tracer Team Switzerland’s E-Tracer won in the Alternative classes.

Google Lunar XPRIZE (Not Won): Targeted private teams to land a rover on the moon. Although the prize expired in 2018 without a winner, several teams continued their lunar missions.

Global Learning XPRIZE (2019): Sought solutions for children to teach themselves reading, writing, and arithmetic. The prize was jointly awarded to Kitkit School and onebillion, both developing child-friendly learning applications.

Nokia Sensing XCHALLENGE (2014): Focused on health sensing technologies. The DMI team won for their invention of a lab-quality blood testing platform.

Carbon XPRIZE (2021): Aimed at converting CO2 emissions into valuable products. Two teams, CarbonCure Technologies and UCLA CarbonBuilt, won, demonstrating concrete production methods using CO2.

Shell Ocean Discovery XPRIZE (2019): Aimed at advancing deep-sea technologies. The GEBCO-NF Alumni team won, developing autonomous ocean mapping technology.