Andy Murray isn't content with being the second-highest ranked tennis player in the world, with career winnings of more than $43 million - and estimated earnings of almost double that amount - he's also dabbling in everything from mortgages to ice cream, by investing in start-ups.
Murray has announced five investments through crowdfunding platform Seedrs - which he provides strategic advice and celebrity endorsement for.
He has put money into Oppo Ice Cream, voted 2015 Start-up of the Year. The investment was part of a hugely successful fundraising initiative. The low calorie luxury ice-cream brand met its fundraising target of £150,000 in just four hours.
He also invested in CommuterClub, an annual travel ticket subscription service. The idea is to enable people to buy annual tickets through a monthly direct debit - taking advantage of the savings of a season ticket, without the terrifying annual lump sum payment. It works by providing a peer to peer loan for customers - paid off through the monthly direct debits. To date, the company has raised £350,000 of its £650,000 target
He has invested in We Are Colony, a global film streaming platform by BAFTA-winning filmmaker Sarah Tierney, which creates special edition bundles of films with exclusive extras. It is currently raising £500,000 and hit 70% of its target within a fortnight.
And finally, he has put money into Readbug, which offers a curated selection of independent magazines in one app. The company met its funding target of £50,000 within a week.
Murray said: "Giving recognition and support to British entrepreneurs is important to me, especially those who are the driving force behind growth-focused businesses. Every one of these entrepreneurs is inspirational and dedicated to their business and I'm excited to have invested in their team's vision and work ethic."
He has said he will announce further investments later in the year, but this is just one of many business interests - which have been flourishing for the past few years. Most famously he bought Cromlix House in Kinbuck, Perthshire, in 2013 and turned it into a luxury hotel.
However, he also has his own management company, 77, and since last year he has started investing in small UK businesses. Last summer he announced undisclosed stakes in Tossed, the salad bar chain, Trillenium - a 3D virtual shop, and the Fuel Futures Fund.
Murray has said he doesn't want to be playing the circuit after he retires, and wants to branch out into other areas instead. Now he has reached the grand old age of 28, we may be seeing where those other interests lie.
It's fair to say, however, that given his world ranking, and his recent announcement that he will lead Great Britain in their defence of the Davis Cup, he's fairly unlikely to be leaving the tennis scene in the immediate future.