"We've just returned from the supermarket. My wife decided to start the day by driving to the store and back," said columnist Tawfiq Alsaif on his Twitter page.
"My wife, Maha, and I have just come from a 45-minute drive. She was the driver through Riyadh streets," said Mohammad al-Qahtani, president of the Saudi Civil and Political Rights Association, in another tweet.
Many Saudi women had pledged on Facebook and Twitter to answer the call to defy the deeply entrenched ban, in the largest such mass action since November 1990, when women demonstrators were arrested and severely penalised.
Instead of staging demonstrations, which are strictly banned in the absolute monarchy, women with driving licences obtained abroad were encouraged to take individual action.
Veteran women's rights activist Wajiha al-Huwaider told AFP on Friday that she did not expect a huge turnout as hoped for by sympathisers abroad because of the severe response by officials to women who have taken the lead in recent weeks.
"I do not expect something big as people abroad imagine," she said, adding that jailing activist Manal al-Sherif and others has scared some women off.
Sharif, a 32-year-old computer scientist, found herself behind bars for two weeks last month after driving in the Eastern Province and posting footage of her actions on the Internet.
Six other women were also briefly detained after being caught learning to drive on an empty plot of land in north Riyadh.
Women in Saudi Arabia face an array of constraints, ranging from having to cover from head to toe in public and needing a male guardian's permission to travel, to having restricted access to jobs because of strict segregation rules.