Where are they now: What's keeping past presidents and vice presidents wealthy?

Presidents and vice presidents don't have to pound the pavement looking for work after leaving office. Thanks to taxpayer-funded lifetime salaries and expense accounts, these public servants can live comfortably in retirement. However, many use their time to write memoirs and influence pet public service projects.

President Obama's net worth of $12.2 million stems largely from his success as an author. Since 2005, he has made more than $15.6 million from the books he authored prior to entering the White House. After leaving office, Barack Obama will no doubt have the opportunity to add to his fortune with high-paying speaking engagements, book deals and spokesperson work for social projects. Additionally, President Obama has expressed an interest in activism, returning to law and even owning an NBA team in the future.

Boasting a more modest net worth of $900,000, Joe Biden also intends to use his influence for good. The vice president, who lost his 46-year old son Beau to brain cancer in 2015, plans to devote his life to promoting cancer research.

As the swearing in of Donald Trump on Inauguration Day on Jan. 20 approaches, let's take a look at some other notable former presidents and vice presidents to see what they've been up to since leaving office.