
5F.com just closed at $56,000 on GoDaddy auctions. The valuable domain name changed hands back in 2011 for $11,000 at Sedo.
Checking out Archive.org it looks like this was a developed website. It was an Asian based Casino website.
There is a freight company using 5F.app and apply5F.com they might be a potential buyer but the pricing will be the key if the auction does not get rolled back.